CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is related to provisional patent application Serial No. 60/108,993, filed Nov. 18, 1998, the contents of which are incorporated herein by reference. 
     This application is also related to the following, commonly assigned patent applications filed concurrently herewith: Ser. No. 09/412,595, now U.S. Pat. No. (6,256,676 B1) for an “Agent-Adapter Architecture for Use in Enterprise Application Integration, Systems”, and Serial No. 09/412,633, now abandoned, for a “Message Object for Use in Enterprise Application Integration Systems”, both of which are incorporated herein by reference. 
    
    
     COPYRIGHT NOTICE 
     Portions of the disclosure of this patent document may contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related generally to what has become known in the computing arts as “middleware”, and more particularly to a unique agent-adapter architecture used in systems and methods to integrate applications of the type normally deployed across a networked enterprise. 
     2. Statement of the Prior Art 
     According to one observer, if the lifeblood of today&#39;s corporations is information, then their arteries are the “inter-application interfaces” that facilitate movement of data around the corporate enterprise. This has more recently become known as an “application network”. 
     For the typical organization, the application network has grown organically into a collection of ad hoc application integration programs. This menagerie has had a very serious impact on businesses as it increases the time for implementing new applications, prevents senior management from getting a clear picture of the business and, in short, clogs the corporate arteries. In spite of the fact that application integration has become crucial to a competitive corporation&#39;s survival, it has nevertheless been acceptable in the prior art to handcraft or “hack” custom code for such purposes at enormous long-term cost to the corporation. Long-term application integration decisions have, likewise, been made at the lowest possible levels based solely on individual project criteria. Because of the decidedly difficult nature of these problems, an effective enterprise application integration (EAI) solution has yet to be found. 
     The advent of the Internet, client/server computing, corporate mergers and acquisitions, globalization and business process re-engineering, have together forced corporate information technology (IT) departments to continually seek out new, and often manual, ways to make different systems talk to each other—regardless of how old some of those systems may be. In the ensuing chaos, inadequate communications systems have had a debilitating effect on IT&#39;s abilities to move as fast as the business needs it to. 
     Recent trends in IT have only exacerbated this problem by increasing—often by an order of magnitude—the amount of inter-application interfacing needed to support them. Most recently, enterprise applications have performed such functions as data warehousing and enterprise resource planning (ERP), and facilitated electronic commerce. A brief review of these three technologies would, therefore, be helpful in understanding the long-felt but as yet unresolved need for EAI. 
     Data warehousing techniques require large volumes of clean historical data that must be moved, on a regular basis, from many operational systems into the warehouse. Source data is usually structured for online transactional processing (OLTP), while the typical data warehouse also accommodates online analytical processing (OLAP) formats. Therefore, the source data must undergo extensive aggregation and reformatting as it is transferred to the warehouse. 
     A typical data warehouse according to the prior art is populated in four steps: (a) extracting the source data; (b) cleaning such extracted data; (c) aggregating the cleaned, extracted data in a number of dimensions; and (d) loading the warehouse. Each warehouse source requires the building of a specific data extraction, cleansing, aggregation, and load routine. Forrester Research estimates that the average large company has approximately four data warehouses. In two years, it is expected that this number will grow to six. The average amount of data contained in each warehouse is also expected to double in size in that same period—from about 130 gigabytes to about 260 gigabytes. 
     The problems associated with such large amounts of data growing at an ever-increasing pace is exacerbated by the quality of source data. According to a study conducted by the META Group, typical data warehouses are being loaded today with as much as 20% poor quality data. That same study indicates that about 70% of its respondents used extraction, cleansing and loading processes that were coded by hand. With respect to the required aggregation processes, anecdotal evidence also reveals that as much as 50 hours of computer time may be required to complete this function alone. It is readily apparent that significant maintenance efforts would be involved with programs coded in such a manner. 
     On the other hand, typical ERP systems (such as the R/3 enterprise application developed by SAP AG of Walldorf, Germany, as well as those developed by PeopleSoft, Oracle, and Baan) are essentially large, integrated packaged applications that support core business functions, such as payroll, manufacturing, general ledger, and human resources. Large corporations find it particularly attractive to buy such software solutions from a single source, since it can cost between 10 to 20 times more to develop the same functionality in-house than to purchase it. Implementing an ERP system, however, can be an overwhelming process for a number of reasons. 
     First and foremost, the corporation is buying a product and not building a solution. This means that business units within the corporation must adapt to the product and how it works, not the other way around. Furthermore, today&#39;s ERP systems cannot replace all of a corporation&#39;s custom solutions. They must, therefore, communicate effectively with other legacy systems in place. Finally, it is not atypical for a corporation to employ more than one and completely different ERP system because a single vendor cannot usually meet every organizational need. 
     As a result, the options for getting data into and out of an ERP system preclude known approaches used for data warehousing. Each ERP system has a proprietary data model that is constantly being enhanced by its vendor. Writing extract or load routines that manipulate such models is not only complicated, but is also discouraged by the vendor since data validation and business rules inherent in the enterprise application are likely to be bypassed. Instead, ERPs require interaction at the business object level which deals with specific business entities such as general ledgers, budgets or accounts payable. Further details regarding implementation and use of one well-known and widely accepted ERP system may be found in  Special Edition Using SAP R/ 3 (2d ed.), ISBN: 0-7897-1351-9, by Que Corporation (1997), the contents of which are incorporated herein by reference. 
     Electronic commerce in one form or another has been around for many years. In essence, it got its start with electronic data interchange (EDI). EDI permitted companies to communicate their purchase orders and invoices electronically, and continued to develop such that today&#39;s companies use EDI for supply chain management. However, not until the more recent exploding use of online Internet websites to buy, sell, and even auction, items of interest has there been such a dire need for robust, effective EAI. See, e.g., U.S. Pat. No. 5,627,972. 
     Applications get developed in order to accomplish a specific business objective in a measured time frame. In a typical large organization, different teams of people using a wide assortment of operating systems, DBMSs and development tools develop hundreds of applications. In each case, the specific requirements are satisfied without regard for integration with any other applications. 
     Several powerful trends are driving the market for application integration. For example, significant developments in peer-to-peer networking and distributed processing have made it possible for businesses to better integrate their own functional departments as well as integrate with their partners and suppliers. The aforementioned Internet/“intranet”/“extranet” explosion is also fueling the demand for a new class of “human active” applications that require integration with back-end legacy applications. Tremendous growth around the world in the adoption of enterprise application software packages (e.g., SAP R/3) also requires integration with back-end legacy applications. Finally, message oriented middleware (MOM)—products such as IBM&#39;s MQSeries message queuing product—are becoming increasingly popular. Once customers realize the benefits of simple one-to-one application connectivity with MOM, their interest in many-to-many application integration increases significantly. 
     As the need for businesses to integrate grows, the number of IT dollars spent on integrating applications is increasing rapidly. According to various industry analysts, the need for “mission critical” application integration will drive the combined market for MOM and “message brokers” to grow from $300 million in 1997 to over $700 million in 1999. According to an IBM survey of larger customers, nearly 70% of all code written today consists of interfaces, protocols and other procedures to establish linkages among various systems. Savvy IT executives can clearly see the dollar savings to be gained by acquiring off-the-shelf software to satisfy as much of this requirement as possible. 
     A message broker is a software hub that records and manages the contracts between publishers (i.e., senders) and subscribers (i.e., receivers) of messages. When a business event takes place, the application will publish the message(s) corresponding to that business event. The broker reviews its lists of subscriptions and activates delivery to each subscriber for that message type. Subscribers receive only the data to which they subscribe. A message published by one application can be subscribed to by multiple consumer applications. Similarly, a subscribing application can receive messages from multiple publishing applications. 
     Before applications can publish or subscribe to messages, they must register their interest with the broker. There are two basic and different methods for applications to register interest in a message type—subject-based addressing and message-content filtering. In subject-based addressing, the broker uses the subject to identify and route the message to all parties expressing interest in that subject. The subject is a word used to describe the contents of the message. For example, a subject of the name “hr. emp. new,” could serve to distribute information (name, address, employee number, etc.) on a newly hired employee. In message content routing, on the other hand, subscriptions are made based on the contents of fields within the message. The subscriptions can be based upon the message type and/or specific selection criteria relative to a field within the message. For example, a loan approval application could subscribe to all purchase orders over $100,000. 
     One advantage to having two publish/subscribe paradigms is that the need to address messages to individual subscribing applications is avoided. Additionally, new subscribing applications can be added without any changes to the publishing application. 
     The typical publishing/subscribing broker uses a robust delivery vehicle for the actual distribution of messages between applications. As mission critical messages travel over a combination of external and internal networks, the systems software ensures that messages are never lost or duplicated in the event of network failures. More often than not, an asynchronous message delivery capability is provided which uses store-and-forward message queuing. In this paradigm, the queue-to-queue transfer takes place in pseudo-real time when the subscribing application is available. If the subscribing application is unavailable, the message is stored in a persistent queue for later delivery. 
     To be effective, the message delivery vehicle must include a business transaction coordination function. A business transaction is typically made up of several units of work. Each and every unit of work must complete in order for the transaction to occur. If even one unit of work fails, the whole transaction fails, and all completed units of work must then be reversed. These transactions are long running and require message-based updates to multiple databases. The business transaction coordination function provides this managerial support. 
     Two other important components are the rules-based engine and the data-transformation component. The business rules engine allows organizations to process messages based upon the unique requirements of their business. Typically, business rules engines provide a visual front end to avoid the need for programming in a procedural language. With this flexible approach, changes in business processes can be easily reflected in a modified rules configuration. 
     The data transformation component is used to develop application-specific adapters. These adapters convert the data formats and applications semantics from the sending application to the receiving application. There are many conversion requirements. They range from basic data transformation to resolving the incompatibilities that exist between the structure (syntax), meaning (semantics) and timing of the information that must be shared. 
     There are two main strategies for application adapters according to the prior art. One strategy is to convert all of the source data and synchronize (or “sync”) applications to a standard canonical form. Messages move from the source adapter to the sync adapter in this standard form. At the sync adapter, the messages are converted to the format of the sync application. 
     The second strategy for application adapters is to automatically convert the format and semantics from the sending application to the receiving application in one step, without any intermediate formats. In this approach, only one adapter is required for two applications to communicate with each other and it can be integrated with either of the applications. 
     The rules based engine and the data transformation component work together to reconcile the differences between applications. For example, before two applications can be integrated around an order, the business rules regarding the processing of orders must be defined within each system. Within Application “A,” an order might be comprised of a collection of data from multiple files and databases; whereas within Application “B,” an order might exist as an individual message nested within a larger file of business transactions. The difficult challenge is to resolve the incompatibilities between the structure of the data and the underlying content of an order as defined in each application. 
     There are a number of potential business benefits that message brokering provide. First of all is their ease of application integration. With message brokers, the integration of new applications with existing legacy or third-party applications can be performed in a shorter period of time. The integration can take place without any need for understanding the internal structure and design of each application. By focusing on the interface as messages, existing applications can be integrated with minimal disruption. 
     Support for electronic commerce is a second benefit that message brokering provides. As businesses begin to automate the supply chain of their vendors and partners, there is a need for their independent applications to communicate in a loosely coupled manner. This is precisely the essence and strength of message brokering. The message broker is completely congruent with the business need. 
     Last, but certainly not least, is message brokering&#39;s support for continued heterogeneity. As new technology has evolved, new architectures have been developed and heterogeneity is increasing over time. A methodology such as message brokering is designed to accommodate today&#39;s heterogeneous world and will be useful in the future. New, differing applications can be added over time as either publishers or subscribers, without any changes to the existing applications in the message broker. 
     In summary, message brokers have the potential to provide a least-common-denominator approach to integrating heterogeneous applications within an enterprise. Users can choose the best technology for each individual application whether JAVA, ACTIVE X, or CORBA, without concern for how that application will integrate with other applications in the enterprise. Message brokers thereby bridge the gap between applications of the future and the disparate and complex products and technologies that currently exist in today&#39;s application catalogues. 
     While there are many benefits to adopting a message broker strategy, it must be kept in mind that there are also potential pitfalls. The very strengths of the message brokering in terms of its loose coupling flexibility, may also be its greatest weakness. The nature of message broker software, as noted above, is very generalized. Because it is designed to handle so many different conditions, testing all possible end-to-end code paths is an insurmountable task. When undetected bugs exist in the software, messages may be lost, delivered twice or delayed. The damage from such “accidents” would be most keenly felt in enterprises where message brokers are used to integrate mission critical transaction processing applications. In financial transactions, for example, the delivery of one single message could be worth millions of dollars; while at the same time its non-delivery or delayed delivery could result in the loss of millions. 
     A second risk to a message broker implementation is the possibility that foreign applications will introduce unauthorized messages to the broker. This may also result in loss. For example, in the banking industry, counterfeit messages could be published and thereby cause the withdrawal or misappropriation of funds. 
     A third risk of message broker implementation is the classical, “single point of failure.” Message brokers of the prior art are typically implemented in a “hub and spoke” architecture. This means that the majority of message traffic passes through a few central hubs. In the event of an outage or a physical disaster to one of those hubs, the mission critical operations of a business could come to a grinding halt. 
     Another problem with distributed hubs is the difficulty of managing the message broker complex. Because a message broker integrates so many different business applications into a few consolidated hubs, the talent and expertise required to manage and administer a message broker complex may be unattainable. 
     The potential risk exposure is large whenever technology is applied to mission critical transaction processing applications of an enterprise. One problem for message brokering is that it manipulates mission critical information. In relative terms, message brokering is fairly new. However, while some early adopter companies have had great success with the concept of message brokering, much more is needed before message brokers and EAI can enter the mainstream. 
     In the 1980&#39;s software systems development concentrated on the ability of heterogeneous systems to communicate with each other. This was, in large part, due to the proliferation of proprietary communication protocols. Any newly developed system had to either comply with the application and data formats in place for the systems with which it wished to connect or communicate, or provide such application a specific translation. Accordingly, all software was customized to a greater or lesser degree. 
     In today&#39;s rapidly changing environment, the concerted efforts of thousands of developers worldwide are focused on developing a system that satisfies the need for disparate applications to communicate with each other, without the necessity of embedding multiple, customized application-specific translation schemes. This as yet unfulfilled need is grounded in the imperative of the global economy. 
     SUMMARY OF THE INVENTION 
     Definitions 
     The following terms should be construed by those of ordinary skill in the art in accordance with their ordinary and accustomed meaning. To the extent the definitions, which appear herein below, differ from otherwise conventional definitions that may be known to those of ordinary skill in the art, it should be appreciated that such terms are hereinafter clearly set forth in such a manner to put one reasonably skilled in the art on notice that the applicant intended to so redefine that claim term. 
     An “accessor” is a function specified in message definitions that the system uses to access data. Accessors identify the start and end of application data fields and system message elements, and remove or insert markers. 
     “Adapter implementations” are code designed for a specific application that can either extract data and produce system messages, receive system messages and update data, or extract data in response to requests. When the user creates an adapter to use in an integration flow, the user builds it around an adapter implementation. System adapter implementations provide basic exception handling and can handle any message definition. The user can create the user&#39;s own custom adapter implementations using the ADK. 
     “Adapters” are integration flow objects that interact with enterprise applications to extract data or insert, update, or delete data. 
     The “administration console” is a graphical user interface (GUI) through which a system administrator configures and manages the system&#39;s nodes and services. 
     “Agent services” provide system services to the adapters. An agent service is required on each host that runs an adapter. 
     A “classpath” is an environmental variable that tells the Java virtual machine where to find the class libraries, including user-defined class libraries. 
     “Clients” are processes that remotely access computer server resources, such as compute power and large memory capacity. Typical system clients are the integration workbench  120  and the administration console  160 . 
     A “connection” is an object that specifies startup or connection parameters for adapters. For example, an RDBMS connection specifies the JDBC driver, the URL of the database, the user name, and password. 
     “Convert” data is a process in which converters specified in message definitions convert an application&#39;s native data types to the Java data types the system supports, and vice versa. 
     A “converter” is a function specified in message definitions that the system uses to convert data. In such a manner, converters convert native data types to the Java data types that the system supports, and vice versa. 
     “Custom adapter implementations” are code designed for a specific application that can either extract data and produce system messages, receive system messages and update data, or extract data in response to requests. Custom adapter implementations, created using the ADK, can connect to applications the system does not currently support. 
     A “definition object” is an integration flow object that provides instructions for a process that the system is to implement. 
     “Delimiters” are tokens or markers that separate data fields in data from enterprise applications. 
     A “durable subscription” is a property of the system&#39;s message hubs that ensures the hub target objects receive all messages intended for them. If a target object becomes inactive, the system remembers those messages, which the target has received. When the target next becomes active, the system delivers messages the target has not yet received. 
     “Enterprise applications” are applications from which adapters extract data or to which adapters propagate data (e.g., SAP R/3 or MQSeries). 
     An “Enterprise Messaging Service (EMS)” according to the present invention is implemented using the Java Messaging Service (JMS). It enables the system to use multiple messaging modes, and supports message hubs and provides message persistence. 
     “Enterprise Resource Planning (ERP)” applications provide a turnkey solution (e.g., warehouse management, human resource management, and materials management) for common business problems. Examples of ERP products are SAP R/3, PeopleSoft, and Baan. 
     An “EntireX Broker (ETB)” is a cross-platform, message-oriented middleware according to the present invention, which links mainframe, Windows NT, and UNIX applications and components, Internet and intranet clients, and ActiveX- and Java-enabled workstations. 
     “Filter definitions” are definition objects that specify criteria for screening messages out of integration flows. 
     A “functions host” is a computing platform, such as a Windows NT server or workstation, or OS/390 mainframe. 
     “Hubs” are integration flow objects that receive messages from source objects and hold the messages until the system delivers them to specified target objects. Hubs allow adapters and transformers to exchange messages asynchronously. They are also useful for concentrating message flows; multiple objects that produce the same kind of message can all send those messages to one message hub, which simplifies links among objects 
     An “IDoc Extractor” reads flat files produced by the SAP R/3 transaction WE63 to create implementation configurations and message definitions and stores them in the the system&#39;s repository service. 
     “Implementation settings” are runtime parameters for adapters (e.g., a polling interval). 
     An “integration flow” is a series of linked system objects that move data from one or more enterprise applications to other enterprise applications. 
     “Integration objects” are integration flow objects, which send messages, receive messages, or both. See, e.g., adapters, hubs, and transformers. 
     An “integration workbench” is a graphical user interface (GUI) through which a user designs integration flows. 
     “Intermediate documents (IDocs)” is an SAP R/3 data format used by R/3 to exchange data with other R/3 systems and with other applications. 
     An “item message element” is a message element that contains data. Items are the lowest level message elements in the hierarchy of the message definition. They cannot contain other message elements. 
     “Java Database Connectivity (JDBC)” is the Java API standard for SQL-based database access. 
     A “Java Development Kit (JDK)” is a software development environment for writing applications in the Java programming language. 
     “Java Message Service (JMS)” is a Java API specified by Sun Microsystems for messaging. 
     A “Java Naming and Directory Interface (JNDI)” is a set of APIs that assist with the interfacing to multiple naming and directory services. 
     “Java Runtime Environment (JRE)” is a subset of the Java Development Kit used to redistribute the runtime environment consisting of the Java virtual machine, Java core classes, and supporting files. 
     A “Java virtual machine (JVM)” is part of the Java Runtime Environment responsible for interpreting bytecodes. 
     “Link markers” are tokens or delimiters that separate data fields in data from enterprise applications. 
     A “message definition category” is a logical grouping for message definitions. 
     “Message definitions” are definition objects, which identify data the system is to extract from or propagate to an enterprise application. Message definitions also define how the system is to construct system messages from enterprise application data or create enterprise application data from system messages. 
     A “message element” is a data object that makes up the message schema of a message definition. Message elements are arranged in a hierarchical structure, and can be sections, tables, or items. 
     “Message-Oriented Middleware (MOM)” is software that uses messages to enable applications on the same or different platforms to communicate. Communications protocols are hidden from the applications. Examples of MOMs are MQSeries, EntireX Broker, and JMS. 
     “Message persistence” relates to the storing of messages onto recoverable media. The system writes each message it delivers from one integration object to another to stable storage in a location the user specifies. If a system failure occurs while a message is in transit, the system can retrieve the message from storage when the system is restored and deliver the message to its targets. 
     A “message schema” is that part of message definitions, which define how to structure a message. Message schemas can include section, table, and item message elements arranged in a hierarchical structure. 
     “Monitor services” store system runtime data, including system logs and statistics information. 
     A “node” is a physical process (or Java virtual machine) that supports one or more system and application services. 
     “Node hosts” are software than enables the user to configure and run nodes on a machine. The user must install a node host on every machine, other than the node manager, that will host a node. 
     A “node manager” is an interface through which nodes are managed. The interface allows the user to configure, start, pause, or stop a service. Node managers start and stop nodes as well. The node manager maintains the state of all of the services that are distributed to the nodes. In addition, the node manager maintains status information (e.g., current state or activity level) of a node or service. 
     “Point-to-point messaging” is a messaging style for hubs in which the system delivers each message that arrives at the hub to a single hub target only (i.e., the first available target. 
     A “primary input message” is the main input data to the system transformation processes specified in transformer definitions. The system takes input data, transforms it, and creates output data needed by target applications. 
     “Publish/subscribe messaging” is a messaging style for hubs in which the system delivers each message that arrives at the hub to all hub targets. 
     A “replier” is a system object, such as a reply adapter, which provides data when transformers request it during the data transformation process. 
     “Reply adapters” are integration objects that reply to requests for data from other integration objects by extracting the data from applications and sending it to the requesting objects. Requesters send system messages containing data in key message elements, and the reply adapters insert data into related message elements and send the system messages back. 
     A “repository service” is interfaced via Java Native Directory Interface, and stores configurations for all configured services and integration flow objects. 
     “Routing services” enable the system to direct messages through the system based on a message&#39;s content, including filtering message content according to criteria the user define. The routing service supports filters. 
     A “system message” is a message, in platform-neutral format, that the system uses to move data from application to application. 
     “Section message elements” are non-repeating groups of message elements that do not contain actual data. They contain other message elements that contain data (i.e., they contain items). Sections can contain any combination of message element types. 
     A “service” is a process that provides product functionality. The system is made up of system, messaging, integration, and agent services. 
     “Source adapters” are integration objects that extract data from enterprise applications, construct system messages from the data, and send the messages to other the system integration objects. 
     A “source object” is an integration flow objects that provides messages to other objects. See, e.g., source adapters, transformers, and hubs. 
     “Supporting input messages” are optional input data to the system transformation processes, as specified in transformer definitions. Transformation processes use supporting input message data to supplement primary input message data. The system takes input data, transforms it, and creates output data needed by target applications. 
     A “table message element” is a group of section message elements, called rows, that can repeat any number of times. Table elements do not contain actual data. Instead, they contain other message elements that contain data (i.e., they contain items). Tables can contain any combination of message element types. 
     “Target adapters” are integration objects that receive system messages from other integration objects, create application data from the system messages, and propagate the data to target applications. 
     A “target integration object” is an integration flow object that receives messages from other objects. See, e.g., target adapters, transformers, and hubs. 
     “Transaction Processing Monitor (TPM)” is a software system designed to optimize use of computing resources, such as storage and applications, for many users. 
     To “transform data” is a process in which transformers modify data taken from one or more enterprise applications into data needed by other enterprise applications. 
     “Transformation services” enable the system to transform messages, including splitting messages, combining messages, and manipulating message data. The transformation dervice supports transformers. 
     A “transformation step” is a command that makes up the transformation process. Each step either reads input message data, transforms and maps input message data to output message definitions, or writes transformed data to output messages. 
     “Transformer definitions” are definition objects that define how the system is to transform system messages extracted from one or more enterprise applications into system messages needed by other enterprise applications. 
     A “transformer” is an integration object that implements transformer definitions. Transformers gather input messages from source integration objects, transform the content and format of the message data, and produce and send output messages to target integration objects. 
     “User interface services (UIS)” provide the user interface facilities necessary to run the client components (i.e., the integration workbench  120  and the administration console  160 ). 
     OBJECTS OF THE INVENTION 
     Accordingly, it is a general object of the present invention to provide systems and methods for integrating enterprise applications, which at the same time provide comprehensive management, including centralized monitoring, operation and configuration. 
     It is a more specific object of the present invention to provide for improved message tracking and manipulation in such systems and methods. 
     Another object of the present invention is to provide enhanced security in such systems and methods, covering such aspects as authentication, authorization, privacy, non-repudiation, and auditing. 
     Still another object of the present invention is to provide systems and method for integrating enterprise applications that include means for disaster recovery, fail-safe rollover, message replay and dual-site logging. 
     It is also an overall object of the present invention to facilitate fast and simple integration of leading ERP applications, custom/legacy applications, packaged applications, and databases. More specifically, it is also an object of the present invention to reduce or substantially eliminate the need for the expensive custom coding that is traditionally required to integrate applications. 
     Another object of the present invention is to provide an EAI system with a distributed architecture that facilitates the long-term reliability, scalability, flexibility, and extensibility needed by today&#39;s enterprises. 
     Still another object of the present invention is to provide an EAI system which increases an enterprise&#39;s return on investment by enabling the enterprise to leverage its existing IT investments, increase its speed to market, implement solutions and realize benefits more quickly, and reduce its operational costs. 
     Yet another object of the present invention is to provide an EAI system which provides faster access to an enterprise&#39;s customer and billing information so that the enterprise can service its customers more effectively and efficiently, creating stronger, more effective relationships. 
     A further object of the present invention is to provide an EAI system with many-to-many points of integration that substantially eliminates the concerns of conventional hub-and-spoke systems and their single-point-of-failure risks. 
     Still a further object of the present invention is to provide an EAI system, which simplifies the enterprise IT, architecture by providing a central point of integration for virtually all applications and platforms. 
     Yet a further object of the present invention is to provide an EAI system which provides efficient and cost effective information sharing. 
     The methods, apparatus, and articles of manufacture described herein will achieve the above and other objects, advantages, and novel features according to the present invention, while avoiding the problems described herein above. 
     In accordance with a first important aspect of the present invention, the method comprises computer-implemented means for passing messages between a first computer application and a second computer application. Such method generally includes the steps of: (a) providing a first message having a first data structure from the first computer application; (b) publishing the first message to obtain a first published message; (c) converting the first data structure of the first published message to a second data structure to obtain a second message; (d) publishing the second message to obtain a second published message; and (e) providing the second published message to the second computer application. 
     According to a second important aspect of the present invention, the apparatus comprises a system for integrating a plurality of computer applications. Such apparatus generally includes means for routing messages within the system; means for storing a plurality of data transformation configurations and a plurality of rules; means for applying the data transformation configurations to messages; means for applying the rules to messages; and means for routing messages between the means for routing messages within the system and the computer applications and having dedicated means for routing messages for respective computer applications. 
     Alternatively, the apparatus of the present invention comprises a system for integrating a plurality of computer applications. Such system generally includes an enterprise messaging system that passes messages between the computer applications; a database storage system, coupled to the enterprise messaging system, that stores a plurality of data transformation configurations and a plurality of rules; an integration service, also coupled to the enterprise messaging system and comprising a data transformation engine using the data transformation configurations stored in the database storage system and a rules evaluation engine using the rules stored in the database storage system; and a plurality of agent-adapters, further coupled to the enterprise messaging system with each agent-adapter coupled to a respective one of the computer applications to pass messages between the enterprise messaging system and the respective computer application. 
     In accordance with a third important aspect of the present invention, the article of manufacture comprises a computer-readable medium embodying code segments for integrating a plurality of computer applications. Such code segments generally include: (a) a first code segment for passing messages between the computer applications; (b) a second code segment for performing data transformation of messages; (c) a third code segment for applying rules to messages; and (d) a plurality of fourth code segments, each of which passes messages between respective computer applications and the first code segment. 
     The apparatus of the invention also includes a computer programmed with software to operate the computer in accordance with the invention. Non-limiting examples of a “computer” in this regard include: a general purpose computer; an interactive television; a hybrid combination of a general purpose computer and an interactive television; and any apparatus comprising a processor, memory, the capability to receive input, and the capability to generate output. 
     The article of manufacture of the invention comprises a computer-readable medium embodying code segments to control a computer to perform the invention. Non-limiting examples of a “computer-readable medium” in this regard include: a magnetic hard disk; a floppy disk; an optical disk, such as a CD-ROM, a CD-R, a CD-RW, or one using DVD standards; a magnetic tape; a memory chip; a carrier wave used to carry computer-readable electronic data, such as those used in transmitting and receiving electronic mail or in accessing a network, such as the Internet or a local area network (“LAN”); and any storage device used for storing data accessible by a computer. Non-limiting examples of “code segments” include computer programs, instructions, objects, software, or any means for controlling a computer. 
     Other novel and equally important aspects of the present invention will become more apparent from a detailed description thereof, when considered in conjunction with the following drawings wherein: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG.  1 ( a ) depicts an enterprise application integration (EAI) system according to the present invention, as it is incorporated within an environment including legacy systems, packaged software applications, and relational database management systems; 
     FIG.  1 ( b ) illustrates a first scenario in which the system that is shown in FIG.  1 ( a ) is used to integrate an enterprise resource planning (ERP) packaged software application with custom legacy systems; 
     FIG.  1 ( c ) illustrates a second scenario in which the system that is shown in FIG.  1 ( a ) is used to integrate two or more disparate ERP packaged software applications; 
     FIG.  1 ( d ) illustrates a third scenario in which the system that is shown in FIG.  1 ( a ) is used to integrate one or more front-office packaged software applications with one or more back-office packaged software applications; 
     FIG.  1 ( e ) illustrates a fourth scenario in which the system that is shown in FIG.  1 ( a ) is used to integrate data warehouse software applications using two or more disparate relational database management systems (RDBMS) or multi-dimensional database management systems; 
     FIG. 2 is a block diagram of the EAI system that is shown in FIGS.  1 ( a ) through  1 ( e ); 
     FIG. 3 depicts an adapter development kit used in the system that is shown in FIG. 2; 
     FIG.  4 ( a ) illustrates a basic agent-adapter architecture that is useful in accordance with a first embodiment of the present invention; 
     FIG.  4 ( b ) illustrates an extensible agent-adapter architecture that is useful in accordance with a second embodiment of the present invention; 
     FIG. 5 is a block diagram of a typical integration flow according to the present invention; 
     FIGS.  6 ( a ) and  6 ( b ) illustrate design and integration objects used in the system according to the present invention; 
     FIG. 7 illustrates a message schema used in the system according to the present invention; 
     FIG. 8 illustrates a typical transformation process used in accordance with the present invention; and 
     FIGS.  9 ( a ) through  9 ( c ) depict various operating environments in which nodes and services according to the present invention are managed; 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, wherein like reference characters or numerals designate like or corresponding parts throughout each of the several views, there is shown in FIG.  1 ( a ) a simplistic view of an enterprise computing runtime environment  10 . Typical runtime environments  10  use a plurality of packaged software applications, including “back-office” applications  20  for enterprise resource planning (ERP) and “front-office” applications  30  for customer relationship management (CRM), one or more customized legacy systems  40 , and one or more multi-dimensional/relational database management systems (RDBMS)  50 . 
     Throughout the past few decades, business enterprises have designed or bought many large, single-purpose software applications. These “legacy” applications continue to be used, and most often were designed to perform a specific function (e.g., inventory, finance, accounting, sales force automation, and human resources). More recently, substantial investments have also been made by those same enterprises to procure packaged software applications from software developers such as SAP, PeopleSoft, Oracle, and Baan. Each of these packaged software applications enjoyed its own unique strengths. Accordingly, the typical business enterprise used two or more disparate packaged software applications in the same runtime environment. Such packaged software applications were not, in the beginning, designed to share information among themselves. As a result, enterprises had been forced to integrate their disparate packaged software applications with expensive custom code. Such integration efforts often took months, if not years, to complete. 
     Enterprise application integration (EAI) systems, such as the system  100  shown in FIG.  1 ( a ), therefore, became a necessity. However, unlike EAI systems according to the prior art, system  100  comprises a solutions-oriented middleware, which facilitates its users to modify and fully integrate information residing within disparate applications through a single, common infrastructure. It allows the user to move information seamlessly, transparently, and quickly among employees, customers, and suppliers, to achieve maximum productivity. 
     In such a manner, the system  100  provides a reliable store-and-forward messaging system, a capable message brokering facility, and a strong agent-adapter architecture for integrating disparate enterprise applications. It is distributable, designed for easy administration and management, and is targeted to the complete, heterogeneous computing requirements of a large organization. It intelligently links various applications so they can access and share information. It is middleware that adapts to applications, rather than forcing applications to adapt to it. 
     System  100  solves most EAI problems by enabling its users to link ERP applications  20 , packaged applications  30 , custom and legacy applications  40 , and databases  50  throughout the enterprise, with minimal custom coding. When fully integrated, an enterprise can quickly synchronize global businesses and divisions and respond to ever changing market demands. With faster access to customer and billing information, the user&#39;s organization can service customers more effectively and efficiently, creating stronger, more effective relationships. 
     The system  100  is a business-centric enterprise integration solution, with an integration flow design environment that targets the business analyst. The analyst defines the problem in business terms, and the product handles the technical issues. 
     For example, as shown in FIG.  1 ( b ), the common scenario of enterprise resource planning (ERP) integration with custom legacy systems demands that the organization encapsulate complex processes properly within standard ERP implementations—not an easy thing to do. Many corporations choose to implement packaged applications for standard business processes such as inventory and order management. But packaged applications are seldom used for vertical processes. For these purposes, the system  100  is ideal. It provides object interfaces for the ERP systems  22 ,  24 ,  26 ,  28 , as well as wrapper-generation technology for linking to legacy systems  44 ,  48 . 
     The extension of the global supply chain also requires that middleware bridge two or more disparate ERP systems  22 ,  24 ,  26 ,  28  . As illustrated in FIG.  1 ( c ), it can be readily appreciated that nothing may be more important to a business-to-business collaboration. The system  100 , thus, plays a key role by enabling inter-ERP transactions in which business events in one system (e.g., SAP system  22 ) invoke corresponding events in another system (e.g., Baan system  28 ) without exposing the details of the underlying technology. 
     Integration of a corporation&#39;s “front-office” with its “back-office” is an important function, which allows front-office applications that interact with the customer to collaborate with back-end production applications. For example, and referring now to FIG.  1 ( d ), it is critically important that customer-support systems collaborate with ERP inventory modules. System  100 , thus, facilitates integration of best-of-breed front-office and back-office applications seamlessly and transparently. 
     In the data warehouse scenario as shown in FIG.  1 ( e ), data from disparate systems must migrate to a central data warehouse or repository. Moving real-time information from several ERP systems (not shown in FIG.  1 ( e )) to a central relational or multi-dimensional database containing a plurality of different databases  53 ,  56 ,  59  is exemplary of this problem. However, data warehouse developers can leverage the data translation services of system  100 , as is described in greater detail herein below, for real-time data aggregation or other operations. Data is, thereby translated into an understandable and meaningful condition. 
     As illustrated in FIG. 2, system  100  generally comprises a plurality of design components  110  and a plurality of runtime management components  150 . The design components  110 , in turn, more specifically comprise an integration workbench  120 , an adapter development kit (ADK)  130 , and a repository service  140 . The runtime management components  150 , in turn, more specifically comprise an administration console  160 , an integration server  170 , including an enterprise messaging engine  180 , a node services component  190 , a plurality of intelligent agent-adapters  200 . 
     The integration workbench  120  generally comprises a graphical modeling and configuration tool for integration project development. It is used to define events, those messages associated with such events, integration flows, and business rules associated with such integration flows, as well as to identify those agents that publish and subscribe to the defined events. In addition, the integration workbench  120  provides diagnostics for consistency checking and testing integration flows. 
     The ADK  130  is used to configure and generate customized intelligent agent-adapters  200 . Shown in greater detail in FIG. 3, ADK  130  generally comprises an object framework including class libraries  132 , wizards  134 , and templates  136 . The ADK  130  generates objects that can be accessed from conventional development tools. While system  100  includes a plurality of standard intelligent agent-adapters  200  for a wide range of applications and resources, there may be specific applications for which there is no such standard intelligent agent-adapter  200 . In that event, ADK  130  further permits a custom, intelligent agent-adapter  200  to be built by those developers who are more familiar with the published interfaces that are provided by the target application environment. 
     The repository service  140  generally comprises a relational database (which contains all of the specifications for system  100 , meta-data, and message broker service rules), and an interface to that relational database. 
     The administration console  160  is used to configure and manage the runtime environment of system  100 , and generally comprises a graphical console. It serves as a control point for system configuration, maintenance, monitoring, and diagnostics. Through the administration console  160 , each of the individual components of system  100  are managed, including comprehensive services such component initiation and termination, and built-in software distribution. 
     The integration server  170  implements intelligent messaging by triggering and executing integration flows to process events. It executes static and dynamic context sensitive rules that evaluate, modify, and route event data. As noted herein above, integration server  170  includes the enterprise messaging engine  180  comprising a distributed messaging subsystem, which manages all event data. It is, on the one hand, a key component of system  100 . On the other hand, it is largely transparent to any user of system  100 , and generally operates behind the scenes. It supports full persistence, once-and-only-once message delivery, and an in-memory mode for non-critical, high volume message requirements. 
     The node services component  190  manages start/restart recovery, exception handling, and dynamic configuration of system  100 . It provides facilities for automated system installation and remote management across all participating clients and servers. Moreover, it is readily capable of installing and updating components remotely. 
     As noted herein above, the plurality of intelligent agent-adapters  200  include not only those standard intelligent agent-adapters  200  that are distributed with system  100 , but also those custom intelligent agent-adapters  200  that are developed by ADK  130 . Each such intelligent agent-adapter  200 , regardless of its type, generally comprises a runtime interface module connecting a particular one of the external application resources  300  to system  100 . 
     Referring for the moment to FIGS.  4 ( a ) and  4 ( b ), it may be appreciated that such intelligent agent-adapters  200 , in accordance with a particularly important aspect of the present invention, combine the functionality of autonomous agents with adapter technology. The agent component  210  acts as an independent software process, which hosts one or more adapter components  220  (FIG.  4 ( a )), or  222  and  224  (FIG.  4 ( b )). It encapsulates sophisticated functionality such as store and forward caching, filtering, resource pooling, and scheduling. 
     A primary advantage of this agent-adapter architecture is its ability to host complex business logic in order to maintain state and negotiate transactions with the application resources  300 . This ability may be thought of as “conversational mode processing”, which is particularly critical when integrating application resources  300  of a transactional nature. More often than not, data elements that may be required for brokering messages from such application resources  300  are deeply nested within sub-transactions. These deeply nested data elements can, thus, be obtained only by engaging in a conversation with the transactional application resource  300 . Otherwise “primitive” adapters, which have been used in the past, do not adequately address the complex behavior of transactional application resources  300 . 
     As shown in FIG.  4 ( a ), a typical intelligent agent-adapter  200  according to the present invention includes an agent component  210  and an adapter component  220 . On one side of this architecture, the agent  210  conforms to a specified event and messaging model of the system  100 . Adapter  220 , on the other side of this agent-adapter architecture, uses a native application programming interface (API)  310  of a particular application resource  300 , or other suitably published interface mechanism. Together, agent  210  and adapter  220  mediate differences in interface protocols and data structures to provide a uniform, normalized view of the business events that they publish and consume. 
     Unlike past approaches to EAI, the foregoing agent-adapter architecture is extensible. It not only facilitates an ability to seamlessly accommodate changes to existing APIs, but it also continues to enable the use of those existing APIs with legacy systems. Shown more clearly in FIG.  4 ( b ), this extensible agent-adapter architecture generally comprises an agent  210  encapsulating a first adapter A′  222  and a second adapter A″  224 . 
     Adapter A′  222 , for example, corresponds to an application resource  300  having a basic set of APIs A′. On the other hand, adapter A″  224  corresponds to the same application resource  300  having a newer set of APIs A″. Users of such an extensible agent-adapter architecture may thereby choose to simultaneously adapt to both interfaces A′ and A″. For example, the basic set of APIs A′ may correspond to a production environment, while the newer set of APIs A″ may correspond to a pre-production environment of a newer version of a particular application resource  300 . The newer set of APIs A″ could, thus, be tested “live” within system  100 , at the same time that the basic set of APIs A′ will be used to maintain previously tested and proven functionality. In such a manner, this extensible agent-adapter architecture enables perfectly seamless negotiation of incremental changes to the application resource  300  into the integration environment. 
     The manner in which system  100  shares data among enterprise applications is determined by integration flows. As shown in FIG. 5, a typical integration flow  500  uses one or more system messages. Each such message generally comprises a communication in a platform-neutral format to move selected data from software application to software application. 
     Referring for the moment to FIGS.  6 ( a ) and  6 ( b ), it should be noted that integration flow  500  is made up of a plurality of objects  600  as well as links among those objects. Each of those objects  600  performs a specific task, which relates to the system messages that carry data from software application to software application. 
     For example, any given object  600  comprises either a definition object  610  or an integration object  620 . There are three basic types of definition objects  610 , which may be used according to the present invention: (1) a message definition  613 ; (2) a mapping definition  616 ; and (3) a filter definition  619 . Definition objects  610  may be used repeatedly in any given integration flow  500 . For example, the same message definition  613  must be assigned to all objects  600  that will handle system messages produced using that message definition  613 . Moreover, the same filter definition  619  may be used in multiple sections of an integration flow  500 . 
     The message definition object  613  identifies data that the system  100  is to extract from or propagate to an enterprise application  510 ,  520 . It also defines how the system  100  not only will construct system messages from enterprise application data, but also create enterprise application data from system messages. 
     Mapping definition objects  616  define how the system  100  will transform system messages extracted from one or more enterprise applications  510 ,  520  into system messages needed by other enterprise applications  510 ,  520 . 
     A filter definition object  619  defines criteria that the system  100  will use to filter unwanted system messages out of integration flows  500 . In an integration flow that transforms new customer data into invoices, for example, one filter definition object  619  that might be useful would be one in which system messages about customers who have already paid would be filtered out. 
     Integration objects  620 , of which there are three basic types, actually send or receive system messages. The three basic types of integration objects are: (1) an adapter  621 ; (2) a message hub  626 ; and (3) a transformer  629 . Furthermore, there are three basic types of adapters: (a) a source adapter  622 ; (b) a target adapter  623 ; and (c) a reply adapter  624 . 
     A source adapter  622  extracts the data from a source enterprise application  510 , constructs system messages from that data, and sends those system messages to other integration objects  620  (e.g., message hub  626 ). A target adapter  623  receives system messages from other integration objects  620  (e.g., transformer  629  through filter definition object  619 ), creates application data from those system messages, and propagates that data to a target enterprise application  520 . A reply adapter  624  (not shown in FIG. 5) replies to requests for data from some other integration objects  620  by extracting the data from applications  510 , 520 , and then sending it to the requesting object  620 . 
     In general, message hubs  626  are used to receive system messages from one or more source integration objects  620 , and to hold those system messages until the system  100  can deliver the same to one or more target integration objects  620 . 
     Transformers  629  are generally used to implement mapping definitions in three steps. They first gather system messages from source integration objects  620  (e.g., message hub  626 ). After the gathering step, they next transform the content and format of the data contained within such system messages. They finally produce and send output system messages to target integration objects  620  (e.g., target adapter  623 ). 
     Message definitions  613  are the primary objects around which the integration flow  500  according to the present invention is built. When a user creates an integration flow  500 , a message definition is assigned to every object  600  in that flow. A message definition  613  not only identifies the kind of system message that the object  600  is to handle, but it also defines the hierarchical structure or schema of that system message. 
     For example, a message definition  613  must be assigned to every source adapter  622  in the user&#39;s integration flow  500 . Each source adapter  622  knows what kind of message it is to produce, based on the message definition  613  the user has assigned to it. Adapters  621 , hubs  626 , and filters  619  handle just one message definition  613 . Mapping definitions  616  and transformers  629 , on the other hand, are capable of handling multiple message definitions  613 , both as inputs and outputs. 
     Some applications  510 ,  520  can create the Java data types that system  100  supports. In those cases, the source adapter  622  can extract the data types specified in its message definition  613  and store them directly in a system message. Likewise, a target adapted  623  can retrieve the data types from a system message and insert them directly into the application (e.g., target enterprise application  520 ). Other applications  510 ,  520  use a well-defined message format to describe the layout of their native data. In those cases, the message definition  613  for a source adapter  622  must include instructions for creating Java types from the application data. Similarly, the message definition  613  for a target adapter  623  must include instructions for creating application data from the system Java objects. 
     A special kind of message definition  613  (i.e., the request/reply message definition) is used by integration objects  620  such as transformers  629  to request data from other the system objects  610 ,  620 . Message definitions  613  can also specify message validation criteria. System  100  uses this criteria to determine whether system messages produced by adapters  621  and transformers  629  contain valid data (e.g., where the user includes a message definition  613  defining messages, which contains employee payroll information). The user, accordingly, may prevent inaccurate salary data from entering the system  100 . If the message definition  613  contains an item element “Salary”, for example, the user could then define validation criteria for the item stating that the message is valid only when the value in “Salary” is a positive number. 
     The user may organize related message definitions  613  into logical groups called message categories. Suppose, for example, that the user is integrating three applications using the system  100 . The user might group the messages in the user&#39;s project into three message categories, one for each application. 
     The following describes in greater detail those elements that make up system messages and provides further details in regards to message validation. A message definition&#39;s message schema is made up of data objects, called message elements, which are arranged in a hierarchical structure as shown in FIG.  7 . In general, a message schema  700  comprises one or more sections  720 , one or more tables  740 , and one or more items  760 . Either a section  720  or a table  740  must appear at the top of message schema  700  hierarchy. 
     A section  720  is a non-repeating group of message elements. Such section elements do not themselves contain actual data. Instead, they contain other message elements that contain data (i.e., they contain items  760 ). Sections  720  can contain any combination of message element types. 
     A table  740  is a group of section elements, called rows that can repeat any number of times. Table elements also do not contain actual data. They contain other message elements that contain data (i.e., they contain items). Tables  740  can contain any combination of message element types. 
     An item  760  is a message element that contains data. Items  760  are the lowest level message elements in the hierarchy of the message definition. They cannot contain other message elements. 
     Each message definition can contain criteria for validating messages based on that definition. That is, when the user define a message definition, the user can specify criteria that data in individual message elements must meet for a message to be considered valid within the system  100 . 
     The user can specify validation criteria for all levels of a message. That is, the user can specify criteria for message items within sections or within tables. The entire message either passes the validation criteria and continues through the flow, or does not pass and is discarded. If even one row of a table does not pass specified criteria, the entire message does not pass. The system  100  validates every message produced by an adapter  621  or transformer  629  using the validation criteria in the appropriate message definition. 
     Adapters  621  connect with enterprise applications  510 , 520  to extract or propagate data. Each adapter  621  produces, receives, or replies to messages using the message definition the user assigns to it. The system  100  provides standard adapters  621  for the applications  510 , 520  it will integrate. Each standard adapter  621  is either a source  622 , target  623 , or reply adapter  624 , and is designed for a specific agent service type. For example, for EntireX Broker, the system offers an ETB Standard Source Adapter and ETB Standard Target Adapter. Standard adapters are generic. They provide basic exception handling and can handle any message definition. If a standard adapter does not include all code the user needs to interact with an application (e.g., the user wants to specify more detailed exception handling), the user can create a custom adapter using the ADK  130 . The user can also use the ADK  130  to create custom adapters  621  for applications  510 ,  520  not currently supported by the system  100 . Likewise, the user can use the ADK  130  to create custom adapters  621  that connect to any application with a JAVA application programming interface (API). 
     To use a standard or custom adapter  621  in an integration flow  500 , the user must configure it to handle a specific message definition. The user can configure as many of each type of adapter  621  as necessary to handle all messages the user need to include in integration flows  500 . 
     Source adapters  622  extract data from enterprise applications and produce messages that they send to other integration objects. Specifically, a source adapter  622 : (1) polls for or is notified by its application of a particular type of event that has occurred at the application (e.g., data on a new customer has been entered); (2) extracts the data relating to the event from the application; (3) using message definition instructions, constructs a system message from the data; and (4) produces a message and sends it to one or more target integration objects  620 . 
     Target adapters  623  receive messages from other the system objects  610 ,  620  in integration flows  500  and propagate the message data to enterprise applications  510 ,  520 . Specifically, a target adapter  623 : (1) receives system messages from one or more source integration objects  620 ; (2) using message definition instructions, creates application data from the system message; and (3) propagates the data to the target application  520  by inserting new data, updating data, or deleting data as appropriate. 
     Reply adapters  624  extract data from enterprise applications  520  when requested by integration objects  620  such as transformers  629 . Specifically, a reply adapter  624 : (1) receives a request message from an integration object  620 ; (2) extracts the requested data from its enterprise application  520 ; and (3) sends the data to the transformer  629  in a reply message based on the same message definition as the request message. 
     Adapters  621  are hosted by agent services. Agent services provide information adapters  621  need to connect to their applications  510 ,  520  (e.g., passwords and user IDs). The system  100  offers agent services for every enterprise application  510 ,  520  it can integrate. That is, it offers an SAP R/3 agent service, an EntireX Broker agent service, and so on. The system  100  also offers agent services for custom adapters the user create using the ADK  130 . 
     The user needs one agent service for each enterprise application  510 ,  520  the user wants to integrate using the system  100 . For example, if the user wants to integrate three SAP R/3 systems with one RDBMS, the user needs three SAP R/3 agent services and one RDBMS agent service. Each agent service hosts all adapters  621  for the enterprise application  510 ,  520  to which the agent connects. 
     Mapping definitions  616  define a process that transforms messages containing data extracted from one or more applications  510 ,  520  into messages containing data needed by one or more applications  510 ,  520 . Transformers  629  implement mapping definitions  616  by gathering input messages from source objects, transforming the data, and sending output messages to target objects. 
     The transformation process defined in a mapping definition  616  always involves at least two kinds of messages: the primary input message, and one or more output messages. The primary input message typically contains most or all of the data the user want to send in output messages to the target applications. Output messages contain data from the input messages, transformed as necessary for target applications  520 . 
     When the user create a mapping definition  616 , the user identifies the message definition  613  that defines the messages the user want to use as the primary input, and the message definitions  613  that define the messages the user want to produce as outputs. A single transformation process can produce any number of outputs. The user then creates a sequence of steps that define when to read input data, how to transform the input data, how to map the input data from input message definitions to output message definitions, and when to write the transformed data to actual output messages. 
     The user can transform input data in any way necessary to create the output messages the user need. For example, the user can create a transformation expression that specifies concatenating a message item containing a customer&#39;s first name and a message item containing the customer&#39;s last name, because a target application requires the customer&#39;s full name in one data field. On the other hand, the user can create a transformation expression that specifies selecting only certain characters from a message item, or padding a message item with spaces to make it the right length for the corresponding data field in the target application. The user can produce different output messages by writing them at different points in the transformation process. 
     When the primary input message does not contain all data needed to produce the output messages, the user can obtain supporting input for the transformation process using request/reply message definitions. For example, suppose the primary input message the user is using in the mapping definition uses abbreviations for United States state names (e.g., Va. for Virginia). 
     The target application  520  requires full state names. To obtain the full state names needed to produce the output messages, the user would use a request/reply message definition that can send the abbreviations to an application and receive the state names in return. 
     After the user has created a mapping definition  616 , the user can test it to make sure it produces the proper output messages before using it in an integration flow  500 . The user can then assign the mapping definition to one or more transformers  629 . 
     A transformer  629  implements a mapping definition  616 . When the user creates a transformer  629 , the user specify objects  610 ,  620  to use as sources of the primary input message and the objects  610 ,  620  that are to be targets for the output messages. The user also specifies the objects that are to reply to requests for supporting inputs. 
     When the transformer  629  receives a primary input message from a source object, it runs the sequence of steps defined in the mapping definition  616  that make up the transformation process. It reads the primary and supporting input messages, transforms the input data, writes the transformed data to output messages, and sends the output messages to the target objects. 
     FIG. 8 shows a typical transformation process in which the transformer  629  receives a primary input message from a hub  626 , obtains a supporting input message from a reply adapter  624 , and sends two different output messages to two different target adapters  623 . 
     Hubs  626  are message holding areas for adapters  621  and transformers  629 . Hubs  626  allow adapters  621  and transformers  629  to exchange messages asynchronously, and simplify links among objects. 
     For example, the user may have a source adapter  622  that produces messages to a transformer  629 . The user may want the adapter  622  to produce and send its messages regardless of whether the transformer  629  is ready to receive them. The user could set up the adapter  622  to send its messages to a message hub  626 , and set up the transformer  629  to receive the adapter&#39;s messages from that hub  626 . The system delivers messages from a hub  626  to a target object when the target is ready to receive them. 
     Furthermore, the user may have three source adapters  622  sending messages based on the same message definition  613  to five targets. If the user did not use a hub  626 , the user would have to create a total of 15 links among the objects. On the other hand, if the user use a hub, the user would have to create and maintain only eight links. Message hubs  626  can hold one kind of message only (i.e., messages produced from a single message definition  613 ). Targets of hubs  626  have durable subscriptions. The system  100  keeps track of the messages each target object has received from the hub  626 , as well as those that the target object has not yet received. If a target becomes inactive, the system  100  remembers the last message the target received. When the target next becomes active, the system  100  delivers only the messages the target has not yet received. If hub subscriptions were not otherwise durable, target objects would receive messages that arrived at hubs while the targets were active, but would never receives messages that arrived at the hubs when the targets were not active. 
     The user can choose from two messaging styles the user wants the system  100  to use when delivering messages from the hub  626 : (1) point-to-point, where the system  100  delivers each message to the first available target only; or (2) publish/subscribe, where the system  100  delivers each message to every object the user has identified as a target of the hub  626 . 
     If the user wants to screen a certain kind of data out of part of an integration flow  500 , the user must use a filter definition  619 . Filter definitions  619  specify criteria based on message data (i.e., data that passes the criteria continues through the flow), while data that does not pass the criteria is discarded. 
     When the user wants to filter a certain kind of message, the user creates a filter definition  619  and assigns it to one or more links between objects that handle that kind of message. The system  100  applies the criteria in the filter definition  619  to all messages sent along those links. 
     For example, consider the situation in which a hub  626  sends messages containing data on new customers to a target adapter  623 . The user may want only data on customers who have not yet paid to reach the target adapter  623 . In order to do so, the user creates a filter definition  619  that specifies the criterion “Status=Paid”, and assigns it to the link between the hub  626  and the adapter  623 . 
     The user can create one or more filter definitions  619  for each message definition  613  in the user&#39;s integration flow  500 . The user can assign a single filter definition to multiple links, or the user can assign different filter definitions for the same kind of message to different links. 
     For example, consider the situation in which a hub  626  sends messages containing data on new customers to two adapters  623 . The user may want one adapter  623  to receive only data on customers who have paid, and the other adapter  623  to receive only data on customers who have not yet paid. The user creates two filter definitions  619 . One specifies the criterion “Status=Unpaid”, and the other specifies the criterion “Status=Paid”. The user then assign each filter definition to the appropriate link. 
     When the user creates a filter definition  619  for messages that do not contain tables of data, the criteria the user specify affects the entire message. The entire message either passes the filter criteria and continues through the flow, or does not pass and is discarded. 
     When the user creates a filter definition  619  for messages that contain tables of data, the user can specify criteria that affect the entire message or that affect only the data within a table. If the user specifies criteria for message items in a section  720 , the entire message either passes the criteria and continues through the flow, or does not pass and is discarded. If the user specifies criteria for message items in a table  740 , the message continues through the flow with only those rows of data that pass the criteria. Rows that do not pass the criteria are discarded. 
     For example, consider the situation in which a message contains a table  740  with nine rows of data, one for each of nine new customers. If the user set up a filter definition  619  that filters out customers who spent $1000 or less, rows containing data on customers who spent more than $1000 would continue through the flow, while rows containing data on customers who spent $1000 or less would be discarded. 
     After the user has created a filter definition  619 , the user can test it to make sure it works properly before using it in an integration flow. 
     Once the system objects the user wants to use in an integration flow  500  exist, the user can indicate how the user wants the system  100  to route messages among them. To do so, the user sets up links among the integration objects  620 . Each link establishes one object as a source and the other as a target, or one object as a requester and the other as a replier. Source adapters  622  are always message sources. They can send messages to target adapters  623  of the same agent service type (e.g., an SAP R/3 source adapter can send messages to an SAP R/3 target adapter), to message hubs  626 , and to transformers  629 . 
     Transformers  629  can be targets, requesters, and sources. They can receive primary input messages from source adapters  622 , message hubs  626 , and other transformers  629 . They also can request supporting input messages from reply adapters  624  and message hubs  626 , and send output messages to target adapters  623 , hubs  626 , and other transformers  629 . 
     Message hubs  626  can be targets and sources. Target adapters  623  are always targets. They can receive messages from source adapters  622  of the same agent service type, from hubs  626 , and from transformers  629 . 
     By default, the system  100  uses “message persistence”. That is, it writes each message it delivers from one integration object  620  to another to stable storage in a location the user specifies. If a system failure occurs while a message is in transit, the system  100  can retrieve the message from storage when the system is restored and deliver the message to its targets. 
     Because message persistence increases system overhead, the system  100  allows the user to turn off persistence for any integration object  620 . However, if a system failure occurs while messages to or from that object are in transit, those messages might be lost. The system  100  offers other delivery-related options that help the user manage the user&#39;s system resources. The system  100  maintains message holding areas for each integration object in a flow  500 . The user can also control the size of these holding areas. 
     The user can limit the number of messages the system  100  holds for each object at one time, and the user can limit the length of time the system  100  holds each message. If an integration object  620  produces messages more quickly than its targets can receive them, these limits can prevent the object&#39;s holding area from growing to a size that strains system resources. 
     The user designs all integration flows  500  within a project on the workbench  120 . Those integration flows  500  that the user designs and saves (i.e., the definition  610  and integration objects  620  that the user creates, and the links among them) are all stored in the repository  140 . The project is a logical structure that lets the user view the repository  140 . Each installation of the system  100  has one project and one repository  140 . 
     In accordance with another important aspect of the present invention, system  100  comprises a distributed system. That is, the user can run the system components that make up the system  100  on one or more physical machines (i.e., hosts), but all of the components working together as one application. 
     A node is a physical process that runs on a host and supports one or more services. Each node is a Java virtual machine (JVM) and is recognized by the operating system as a javaw.exe process. The user must create at least one node for each host that runs an enterprise application the user want to integrate. The user can have as many nodes as the user&#39;s business requirements dictate. 
     Each enterprise must also have a node manager. The node manager provides services to all of the other nodes in the system. It runs the user interface service (UIS) and the repository service  140 . FIG.  9 ( a ) illustrates an environment that has three hosts. Host 1  runs the Node Manager, and Host 1  and Host 2  are both running nodes. In contrast, Host 1  and Host 2  as shown in FIG.  9 ( b ) are both running services. Host 3  cannot run services because is does not have a node. 
     The system  100  is a collection of system services and application services. System services support nodes and services. For example, the monitor service stores system runtime data for nodes and services. Application services provide the system&#39;s functionality. For example, CICS agent services support adapters that need to connect to CICS applications. 
     System services comprise the following. The user interface services (UIS) provide the facilities necessary to run the client components (i.e., the workbench  120  and the administration console  160 ). The repository services  140  stores configurations for all configured services and integration flow objects. Monitor services store system runtime data, including system logs and statistics information. 
     Application services comprise the following. Enterprise Messaging services (EMS) enable the system  100  to use multiple messaging modes, including point-to-point, publish/subscribe, and request/reply messaging. They support message hubs  626  and provide message persistence. Integration services (IS) enable the system  100  to transform messages, including splitting messages, combining messages, and manipulating message data. The IS supports transformers. RMI Factory manages remote method invocation (RMI) links to external applications. Routing services enable the system  100  to direct messages through the system  100  based on a message&#39;s content, including filtering message content according to criteria the user defines, and determining whether messages are valid. The routing service supports filters. Agent services support adapters  621 . The user must install an agent service on each host that runs an enterprise application the user want to integrate. 
     System  100  also includes two client graphical user interfaces (GUIs) that enable the user to work with integration flows in the following manner. Regardless of whether the host runs the node manager, runs nodes and services, or does not run any nodes or services, the user may run clients on any host. The user may install as many clients as the user&#39;s business requirements dictate. For example, the user might want to install clients on a network-attached host to work with the user&#39;s integration flows  500  from a remote location. As described in greater detail herein below, GUIs on the workbench  120  enable the user to design integration flows  500 . GUIs on the administration console  160 , on the other hand, help configure and manage the system components (i.e., the nodes and services). Referring now to FIG.  13 ( c ), both Machine 2  and Machine 3  can be seen as running the administration console  160  and workbench  120  clients. Machine 1  is not running either of the administration console  160  or the workbench  120 . 
     There are two primary interfaces within the system  100 : (1) the workbench  120  and the administration console  160 . The workbench  120  provides tools for creating and modifying integration flows  500 , while the administration console  160  provides all of tools for managing the system nodes and services. Both are described in greater detail herein below. 
     Integration Workbench 
     Details regarding the installation and operation of integration workbench  120  may be found in the following documentation from SAGA Software, Inc., each of which is incorporated herein by reference: “System Administration Guide” (describes how to use the administration console  160  to configure and manage the system  100 , and provides step-by-step procedures for working with user accounts, nodes, and services, managing the repository, and using log and statistics tools); “Workbench User&#39;s Guide” (describes how to use the integration workbench  120  to integrate application, provides step-by-step procedures for creating objects used in integration flows, and also provides reference material for operators and functions used in integration flows); “Adapter Development Kit Reference Manual” (serves as a reference guide for building custom adapters); “EntireX Broker Adapter Guide” (serves as a reference guide for configuring and modifying EntireX Broker adapters within the agent-adapter framework); “CICS Adapter Guide” (serves as a reference guide for configuring and modifying CICS adapters within the agent-adapter framework); “MQSeries Adapter Guide” (serves as a reference guide for configuring and modifying MQSeries adapters within the agent-adapter framework); “RDBMS Adapter Guide” (serves as a reference guide for configuring and modifying RDBMS adapters within the agent-adapter framework); “SAP R/3 Adapter Guide” (serves as a reference guide for configuring and modifying SAP R/3 adapters within the agent-adapter framework). Further details regarding functions may also be found in the Appendix attached hereto. 
     Creating an integration flow  500  in accordance with the present invention may be done as follows. The user first must obtain agent services from the system  100 . On the administration console  160 , the user then configures the system nodes of each host machine on which an application the user wants to integrate is running. Then, the user configures the required services on the nodes, including an agent service for each application that the user is going to integrate. 
     In order to plan an integration flow, the user should determine the following factors. For example, the user must determine the kinds of data the user need to extract from applications and propagate to applications. The user should also consider: (1) how the user wants to route messages among the system objects; (2) how the user needs to transform the data from one application so it can be used by other applications; and (3) whether the user needs to filter certain data out of the flow. 
     On the workbench  120 , the user should first create a project, and then create an integration flow in the following manner. First, the user should configure adapters  621  to interact with the user&#39;s applications and create the message definitions  613  the user needs to produce the proper messages in the integration flow  500 . These message definitions  613  should then be tested to make sure they produce the proper messages. 
     Next, the user should create hubs  626  to hold messages from adapters  621  and transformers  629 . The user may then create mapping definitions  616  to transform messages from the source application  510  to messages for the target application  520 . Furthermore, the user may create sample input messages and use them to test each mapping definition to make sure it produces the proper output messages. 
     Then, the user should create the transformers  629  necessary to implement those mapping definitions  616 . As needed, the adapters  621 , transformers  629 , and hubs  626  should be linked. If the user needs to filter certain data out of the flow  500 , the user should then create filter definitions  619 . Preferably using sample messages, the user should next test the filter definitions  619  to make sure they filter out and proper data. Then, the user may assign the filter definitions  619  to links between objects. 
     On the workbench  120 , the user should then check the validity of the integration flow  500  and correct it as necessary. The user may then save and close the project. On the administration console  160 , the user should then configure the log viewer so the user can view messages on system activity. If the user wants to view statistics on system activity (e.g., number of messages produced in specific time intervals by individual transformers), the user should then configure the statistics viewer. 
     Again, on the administration console  160 , the user may start the integration flow by starting the relevant system nodes and services, including the agent services for the applications the user is going to integrate. Next, the user will check the log and statistics to make sure the integration flow  500  is running properly. If the user needs to make changes to the integration flow  500 , the user should accordingly stop the relevant services on the administration console  160 , modify the integration flow  500  on the workbench  120 , and restart services on the administration console  160 . 
     The following describes to one of ordinary skill in the art the procedures that may be used with a source adapter wizard, a target adapter wizard, and a reply adapter wizard, all in accordance with the present invention, to properly configure an adapter. In general, there are four separate processes. First, one must carry out the following general steps: (1) naming the adapter; (2) choosing the agent service one desires to host the adapter; and (3) choosing the message definition for messages that the adapter is to produce, receive, or reply to. Second, one must carry out the following general steps: (1) choosing a particular adapter that is to be configured (i.e., standard or custom); (2) providing connection information; and (3) providing implementation information. More often than not, the step of providing implementation information includes the step of extracting the message definition of that adapter. 
     The third process depends on the type of adapter to be created. If one is creating a source adapter, one must specify the targets to which the adapter is to be used to send messages. On the other hand, if one is are creating a target adapter, one must specify the sources from which the adapter is to be used to receive messages. If one is creating a reply adapter, furthermore, one must specify the requesters (i.e., transformers) to which the adapter is to be used to send reply messages. 
     One must finally specify delivery options (e.g., message lifetime) for the adapter&#39;s messages. However, before one can create an adapter, the agent service that is to host the adapter must exist on the administration console  160 . For example, before one can create an EntireX Broker adapter, the agent service for the EntireX Broker must exist. If one wants to also specify source, target, or requester objects for an adapter using the adapter wizard, those objects must exist before one opens the adapter wizard. 
     Referring again to FIGS.  4 ( a ) and  4 ( b ), agent-adapters  200  interface with the application resources on one side and the infrastructure of system  100  on the other. On the one hand, the adapter half of each agent-adapter  200  uses the API of its particular application resource, or any other published interface mechanism. On the other hand, the agent side conforms to the event and messaging model of system  100  as described in greater detail herein below. In combination, the agent and adapter mediate the differences in interface protocols and data structures, providing a uniform, normalized view of the business events that they publish and consume. 
     Unlike other application integration solutions, the extensible design of the adapter architecture provides—the ability to seamlessly accommodate change to application interfaces, while still supporting the current set of basic interfaces. This is particularly important with systems that are already in production. For instance, a packaged application having a basic set of interfaces A′ which are supported by a particular version of agent-adapter  200 . If a newer version of the application incorporates a newer set of interfaces A″, the user may choose to simultaneously adapt to the older interfaces A′ for the production environment, while adapting to A″ for a pre-production environment in order to test the new interfaces. With this facility, incremental change into the integration environment can be negotiated seamlessly. 
     Every component of system  100  is distributable across all supported platforms agent-adapters  200  flexibly extend this to the participating applications. Key components of system  100  (e.g. agent-adapters  200  or Integration Server  26 ) can, thus, be co-located with applications, or accessed remotely, or both. Numerous deployment configurations are possible—the environment is optimized to balance availability, performance and administration requirements. 
     Many standard adapters  200  are supplied with system  100 , including SAP, MQSeries, ENTIRE Broker, RDBMS &amp; CICS. As such, the adapters  200  support rapid deployment and easy integration of these information resources. They also reduce training and skills required. The ADK  130 , including all of its automation wizards templates, provides high productivity. It is adaptable to any user&#39;s IDEs, and it facilitates customizing supplied adapters and developing custom interfaces. The adapters  200  are made up of popular language and interface bindings, including C++, Java, EJB, CORBA, COM, and Natural. In such a manner, they plug into any user&#39;s environment and tools. They leverages in-house language expertise, and they are adaptable to complex resource interface requirements. The agent-adapter architecture according to the present invention, thus, provides a robust facility supporting far more than simplistic interfaces. It ensures a uniform event across the resource portfolio. 
     The agent-adapter subsystem comprises the runtime interface modules that connect external applications to the EAI. On the adapter side, it is the physical interface to the external application. The agent side acts as a host for the adapter, manages resources and publishes events on behalf of the adapter. 
     EAI agent-adapters combine the notion of autonomous agents with adapter technology. The agent component acts as an independent software process that hosts the adaptive technology. It encapsulates sophisticated functionality such as store and forward caching, filtering, resource pooling, scheduling and dispatching. A primary advantage of the agent component is its ability to host complex business logic in order to maintain state status and negotiate transactions with the external application. This is called conversation mode processing and is particularly critical when integrating with transactional systems. Often the data elements required for brokering are deeply nested within sub-transactions and can only be retrieved by engaging in a “conversation” with the transactional system. The “primitive” adapters of the prior art do not address this problem in the complex behavior of transactional systems. 
     The adapter component uses the resource API. The agent component conforms to the EAI event and messaging model. In combination, the agent and adapter mediate the differences in interface protocols and data structures, providing a uniform, normalized view of the business events that they publish and consume. 
     Unlike other application integration solutions, the extensible design of the agent-adapter subsystem of the present invention provides the ability to seamlessly accommodate change to application interfaces, while supporting the basic interfaces. This is particularly important with systems that are already in production. For instance, a packaged application has a basic set of interfaces A′, which are supported by a particular version of an agent-adapter. If a new version of the application incorporates a new set of interfaces A″, the user may choose to simultaneously adapt the older interfaces for the production environment while adapting the A″ interfaces for a new pre-production environment in order to test the new interfaces. The present invention, with its incremental change facility, can negotiate this function seamlessly. Every component of the EAI system is capable of being distributed across all supported platforms. Agent-adapters flexibly extend this to the participating applications. Agent-adapters can be co-located with the applications or be accessed remotely or a combination thereof in order to optimize the environment to balance availability, performance and administrative requirements. 
     The EAI adapters provide communication to third party (external) application packages. There are currently four basic types of message processing supported by any given adapter. Each type of processing is implemented within its own JAVA Class. These classes will serve as base classes to be extended by an application specific implementation. 
     The basic types of communication used by the adapter do not rely on the underlying messaging semantics implemented by the node/agent. They could be used over either pub/sub or point to point protocols without affecting the adapter behavior. The agent will make this determination based on its configuration definitions. 
     The base adapter classes within system  100  are as follows. The “Adapter Main” class provides the ability for the adapter to start itself and process its configuration definitions. It is also responsible for instantiating instances of the classes to be used by the four possible types of adapter communications. The “Adapter Receiver” class provides the ability for the adapter to receive a document from EAI and pass it on to the third party package. The “Adapter Sender” class provides the ability for the adapter to receive a document from a third party package and pass it on to EAI. The “Adapter Responder” class provides the ability for the adapter to receive a document from EAI, pass it on to a third party package, receive a response from the third party package and return the response to the EAI for processing. The “Adapter Requestor” class provides the ability for the Adapter to receive a document from a third party package, pass it on to EAI for processing, receive a response from EAI and return the response to the third party package. 
     The EAI agent-adapter interface according to the present invention is realized by the adapter implementing several JAVA interfaces, while the adapter to agent interface is realized by the adapter using known methods of the node/agent components. 
     According to still another important aspect of the present invention, every adapter must implement the following interface. For the AdapterBridge, the method: 
     initialize(Agent-adapterConfig) 
     is invoked by the agent during initialization and used by the adapter to bootstrap itself. The adapter bridge is within the method that the adapter  220 ,  22 ,  224  must query the agent  210  to determine what document definitions are to be processed and the type of processing provided for each document. This is accomplished using the following agent methods: 
     GetSendDocumentDefinitions( ) 
     getReceiveDocumentDefinitions( ) 
     getRequestDocumentDefinitions( ) 
     getResponseDocumentDefinitions( ) 
     This method will then parse the AdapterConfiguration document to locate the subsection pertaining to the specific document definition, harbor the document specific configuration information and create an instance of a specific class based on processing type (send, receive, request or response). It will subsequently either start a Thread(Send or Request types), issue the Agent.setReceiveListener( )(Receive type) or issue the Agent.setResponseListener( )(Response type) to register the agent callbacks to be invoked when a message arrives. 
     The restart ( ) method is invoked by the agent  220 ,  222 ,  224  to cause the adapter  210  to terminate all activity, reload configuration data and restart itself. The shutdown ( ) method is invoked by the agent  220 ,  222 ,  224  during termination processing. 
     The following interfaces are also implemented by the adapters  200  as described herein below. For the ReceiveListener interface, an 
     onReceiveMessage(ReceiveData) 
     method is invoked by the agent  210  on receipt of a JMS message, and he agent will pass the document on to the adapter for processing. This processing will occur under control of the JMS session thread. The adapter processing will basically consist of a one way routing of the document to the third party software application using the interfaces provided by the application. It should be noted, however, that there is no reply expected from the application on this type of call. The adapter  220 ,  222 ,  224  will be expecting only a success or failure response from the application. If EAI is expecting an actual response from the third party system, the ResponseListener interface should be used instead. 
     For the SendListener interface, an 
     onSendTimerEvent(SendData) 
     method is invoked by the agent  210  if the adapter  220 ,  222 ,  224  is utilizing the timer feature of the node/agent. This feature is useful when the third party interface has no way to implement an event driven notification for documents to be sent to EAI for processing. 
     For the RequestListener interface, an 
     onRequestTimerEvent(RequestData) 
     method is invoked by the agent  210  if the adapter  220 ,  222 ,  224  is utilizing the timer feature of the node/agent. This feature is useful when the third party interface has no way to implement an event driven notification for documents to be sent to EAI for processing. It should be noted at this juncture, however, that the RequestListener interface differs from the SendListener interface, in that it will send the document to EAI and wait for a document in response. This response will then be passed back to the third party system. 
     For the ResponseListener interface, an 
     onResponseMessage(ResponseData) 
     method is invoked by the agent  210  on receipt of a JMS message, and the agent  210  will pass the document on to the adapter  220 ,  222 ,  224  for processing. This processing will occur under control of the JMS session thread. The adapter processing will consist of routing of the document to the third party software application using the interfaces provided by the application and then sending the response back into the EAI system  100  for additional processing. However, if the EAI system  100  is not expecting an actual response from the third party system the ReceiveListener interface should be used instead. 
     The examples shown and described herein above are not meant to limit the scope of the invention. Accordingly, modifications and variations according to the present invention will become apparent to those of ordinary skill in the art, without departing from the spirit and scope of the appended claims. 
     Appendix 
     Operators 
     The following table generally describes all of the currently contemplated system operators, which a user can use to build expressions for message definitions, transformer definitions, and filter definitions. System  100  supports these operators. 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 Operator 
                 Description 
               
               
                   
                   
               
             
             
               
                   
                 &amp;&amp; 
                 Logical “and” 
               
               
                   
                 ∥ 
                 Logical “or” 
               
               
                   
                 ! 
                 Logical “not” 
               
               
                   
                 = 
                 Assignment 
               
               
                   
                 == 
                 Logical “equal” 
               
               
                   
                 != 
                 Logical “not equal” 
               
               
                   
                 + 
                 Unary plus 
               
               
                   
                 − 
                 Unary minus 
               
               
                   
                 * 
                 Multiplication 
               
               
                   
                 / 
                 Division 
               
               
                   
                   
                 Less than 
               
               
                   
                 &lt;= 
                 Less than or equal to 
               
               
                   
                 &gt; 
                 Greater than 
               
               
                   
                 &gt;= 
                 Greater than or equal to 
               
               
                   
                   
               
             
          
         
       
     
     Functions 
     The table following on the next page generally describes all of the currently contemplated system functions, which a user can use to build expressions for validating or filtering messages and transforming message data. Each description includes what the function does, the parameters it requires, and the value it returns. 
     When transforming message data, the user typically uses these functions to take message item values from input messages and create message item values for output messages. When validating or filtering messages, the user usually uses these functions to create boolean expressions. The parameter values for these functions can either be message items or constant (i.e., literal) values. 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 Data Type 
                 Literal Examples 
               
               
                   
                   
               
             
             
               
                   
                 Integer 
                 1234, 0xFF, 077, −1234 
               
               
                   
                 Long 
                 1234, 1234L, −0xFF, 077L 
               
               
                   
                 Double 
                 12.34 
               
               
                   
                 String 
                 “Sagavista” 
               
               
                   
                 Boolean 
                 true or false 
               
               
                   
                 BigDecimal 
                 12.34a, where “a” means arbitrary precision 
               
               
                   
                 Calendar 
                 #DATE(2000, 2, 13) 
               
               
                   
                   
                 #DATE_TIME(2000, 2, 13, 23, 59) 
               
               
                   
                   
                 #DATE_FORMAT(“M/d/yyyy”, “2/13/2000”) 
               
               
                   
                   
               
             
          
         
       
     
     The system  100  also provides the functions described below, although a user can write the user&#39;s own functions for use with system  100 . 
     
       
         
               
               
             
           
               
                   
               
               
                 Function 
                 Description 
               
               
                   
               
             
             
               
                 addToDate 
                 Adds a specified number of days to a Calendar 
               
               
                   
                 object date and returns the resulting Calendar 
               
               
                   
                 object date 
               
               
                 bigDecimalTo Boolean 
                 Converts a BigDecimal object to a Boolean object 
               
               
                 bigDecimalToDouble 
                 Converts a BigDecimal object to a Double object 
               
               
                 bigDecimalToLong 
                 Converts a BigDecimal object to a Long object 
               
               
                 bigDecimalToString 
                 Converts a BigDecimal object to a String object 
               
               
                 booleanToBigDecimal 
                 Converts a Boolean object to a BigDecimal object 
               
               
                 booleanToLong 
                 Converts a Boolean object to a Long object 
               
               
                 booleanToString 
                 Converts a Boolean object to a String object 
               
               
                 calendarToString 
                 Converts a Calendar object to a String object 
               
               
                 compareDates 
                 Compares two Calendar object date values and 
               
               
                   
                 indicates whether the first date is less than, equal 
               
               
                   
                 to, or greater than the second date 
               
               
                 doubleToBigDecimal 
                 Converts a Double object to a BigDecimal object 
               
               
                 doubleToLong 
                 Converts a Double object to a Long object 
               
               
                 doubleToString 
                 Converts a Double object to a String object 
               
               
                 findString 
                 Searches for a String object within another String 
               
               
                   
                 object and returns the position of the found 
               
               
                   
                 String&#39;s first character within the other String 
               
               
                 findWord 
                 Searches for a word within a String object and 
               
               
                   
                 returns the position of the word&#39;s first 
               
               
                   
                 character within the String 
               
               
                 foundString 
                 Searches for a String object within another String 
               
               
                   
                 object and returns a Boolean object 
               
               
                 foundWord 
                 Searches for a word within a String object and 
               
               
                   
                 returns a Boolean object 
               
               
                 getDate 
                 Finds the date in a Calendar object and returns the 
               
               
                   
                 month as an Integer object 
               
               
                 getMonth 
                 Finds the month in a Calendar object and returns 
               
               
                   
                 the month as an Integer object 
               
               
                 getYear 
                 Finds the year in a Calendar object and returns the 
               
               
                   
                 year as an Integer object 
               
               
                 getTokenAt 
                 Parses a String object into tokens, finds a 
               
               
                   
                 particular token, and returns the token as a String 
               
               
                   
                 object 
               
               
                 integerToString 
                 Converts an Integer object to a String object 
               
               
                 isAlpha 
                 Determines whether all characters in a String 
               
               
                   
                 object are alphabetic and returns a Boolean object 
               
               
                 isAlphaNumeric 
                 Determines whether all characters in a String 
               
               
                   
                 object are alphanumeric and returns a Boolean 
               
               
                   
                 object 
               
               
                 isNumeric 
                 Determines whether all characters in a String 
               
               
                   
                 object are numeric and returns a Boolean object 
               
               
                 justifyCenter 
                 Creates a String object of a specified length and 
               
               
                   
                 centers another String object within it 
               
               
                 justifyLeft 
                 Creates a String object of a specified length and 
               
               
                   
                 left justifies another String object within it 
               
               
                 justifyRight 
                 Creates a String object of a specified length and 
               
               
                   
                 right justifies another String object within it 
               
               
                 longToBigDecimal 
                 Converts a Long object to a BigDecimal object 
               
               
                 longToBoolean 
                 Converts a Long object to a Boolean object 
               
               
                 longToDouble 
                 Converts a Long object to a Double object 
               
               
                 longToString 
                 Converts a Long object to a String object 
               
               
                 lookup 
                 Looks up a String object in a lookup table 
               
               
                   
                 specified in another String object and returns 
               
               
                   
                 the corresponding value 
               
               
                 lowercase 
                 Converts all characters in a String object to 
               
               
                   
                 lowercase 
               
               
                 replaceString 
                 Searches a String object for a particular String 
               
               
                   
                 object, replaces the found String object with a 
               
               
                   
                 replacement String object, and returns the String 
               
               
                   
                 object with the replacement String in place 
               
               
                 replaceWord 
                 Searches a String object for a particular word, 
               
               
                   
                 replaces the found word with a replacement word, 
               
               
                   
                 and returns the String object with the 
               
               
                   
                 replacement word in place 
               
               
                 sizeOf 
                 Determines the size of a String object or a 
               
               
                   
                 ByteArray object and returns the size as a Long 
               
               
                   
                 object 
               
               
                 stringToBigDecimal 
                 Converts a String object to a BigDecimal object 
               
               
                 stringToBoolean 
                 Converts a String object to a Boolean object 
               
               
                 stringToCalendar 
                 Converts a String object to a Calendar object 
               
               
                 stringToDouble 
                 Converts a String object to a Double object 
               
               
                 stringToInteger 
                 Converts a String object to an Integer object 
               
               
                 stringToLong 
                 Converts a String object to a Long object 
               
               
                 Subarray 
                 Finds a ByteArray object within another 
               
               
                   
                 ByteArray object and returns the found 
               
               
                   
                 ByteArray object 
               
               
                 substring 
                 Finds a String object within another String 
               
               
                   
                 object and returns the found String object 
               
               
                 trim 
                 Removes white space from before and after 
               
               
                   
                 a String 
               
               
                 uppercase 
                 Converts all characters in a String object to 
               
               
                   
                 uppercase 
               
               
                   
               
             
          
         
       
     
     addToDate 
     This function adds a Long object that specifies a certain number of days to a Calendar object date and returns the resulting Calendar object date. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Calendar addToDate(Calendar,Long) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Calendar,Long) 
                 Date, number of days to add to the date 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Calendar 
                 Resulting date 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a Calendar object. For another message, the user need the value of DatePurchased plus five days in a Calendar object. The user would enter the function as follows: 
     addToDate (MsgDef.DatePurchased, 5) 
     If the value of DatePurchased were equivalent to Feb. 13, 2000, the function would return a Calendar object whose value is equivalent to Feb. 18, 2000. 
     bigDecimalTo Boolean 
     This function converts a BigDecimal object to a Boolean object. 
     
       
         
               
             
               
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean bigDecimalToBoolean(BigDecimal) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (BigDecimal) 
                 BigDecimal to convert 
               
             
          
           
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 BigDecimal is any value other than 0 
               
               
                   
                 False 
                 BigDecimal is 0 
               
               
                   
               
             
          
         
       
     
     bigDecimalToDouble 
     This function converts a BigDecimal object to a Double object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Double bigDecimalToDouble(BigDecimal) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (BigDecimal) 
                 BigDecimal to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Double 
                 Resulting Double 
               
               
                   
                   
               
             
          
         
       
     
     bigDecimalToLong 
     This function converts a BigDecimal object to a Long object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long bigDecimalToLong(BigDecimal) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (BigDecimal) 
                 BigDecimal to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Resulting Long 
               
               
                   
                   
               
             
          
         
       
     
     bigDecimalToString 
     This function converts a BigDecimal object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String bigDecimalToString(BigDecimal) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (BigDecimal) 
                 BigDecimal to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     booleanToBigDecimal 
     This function converts a Boolean object to a BigDecimal object. 
     
       
         
               
             
               
               
               
               
             
           
               
                   
               
               
                 BigDecimal booleanToBigDecimal(Boolean) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
                   
               
               
                   
                 (Boolean) 
                 Boolean to convert 
               
               
                   
                 Return Type 
                 Value 
                 When 
               
               
                   
                 BigDecimal 
                 1 
                 Boolean is true 
               
               
                   
                   
                 0 
                 Boolean is false 
               
               
                   
                   
               
             
          
         
       
     
     booleanToLong 
     This function converts a Boolean object to a Long object. 
     
       
         
               
             
               
               
               
               
             
           
               
                   
               
               
                 Long booleanToLong(Boolean) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
                   
               
               
                   
                 (Boolean) 
                 Boolean to convert 
               
               
                   
                 Return Type 
                 Value 
                 When 
               
               
                   
                 Long 
                 1L 
                 Boolean is true 
               
               
                   
                   
                 0L 
                 Boolean is false 
               
               
                   
                   
               
             
          
         
       
     
     booleanToString 
     This function converts a Boolean object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String booleanToString(Boolean) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Boolean) 
                 Boolean to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     calendarToString 
     There are two versions of this function. 
     The following function converts a Calendar object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String calendarToString(Calendar) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Calendar) 
                 Calendar to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a Calendar object to a String object, using a format mask to format the String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String calendarToString(Calendar,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Calendar,String) 
                 Calendar to convert, format mask 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, in the format specified by the mask 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a Calendar object. For another message, the user need the value of DatePurchased in a String object, in the format M/d/yyyy. The user would enter the function as follows: 
     calendarToString (MsgDef.DatePurchased, “M/d/yyyy”) 
     If the value of DatePurchased were equivalent to Feb. 13, 2000, the function would return a String object whose value is “2/13/2000”. 
     compareDates 
     This function compares two Calendar object date values and indicates whether the first date is less than, equal to, or greater than the second date. 
     
       
         
               
             
               
               
             
               
               
               
             
           
               
                   
               
               
                 Long compareDates(Calendar,Calendar) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Calendar,Calendar) 
                 First date to compare, second date to compare 
               
             
          
           
               
                 Return Type 
                 Value 
                 When 
               
               
                 Long 
                 −1 
                 First date is less than second date 
               
               
                   
                   0 
                 First date is equal to second date 
               
               
                   
                   1 
                 First date is greater than second date 
               
               
                   
               
             
          
         
       
     
     doubleToBigDecimal 
     This function converts a Double object to a BigDecimal object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 BigDecimal doubleToBigDecimal(Double) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Double) 
                 Double to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 BigDecimal 
                 Resulting BigDecimal 
               
               
                   
                   
               
             
          
         
       
     
     doubleToLong 
     This function converts a Double object to a Long object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long doubleToLong(Double) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Double) 
                 Double to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Resulting Long 
               
               
                   
                   
               
             
          
         
       
     
     doubleToString 
     There are two versions of this function. 
     The following function converts a Double object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String doubleToString(Double) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Double) 
                 Double to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a Double object to a String object, using a format mask to format the String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String doubleToString(Double,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Double,String) 
                 Double to convert, format mask 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, in the format specified by the mask 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Discount is defined as a Double object. For another message, the user need the value of Discount in a String object, in the format #.##. The user would enter the function as follows: 
     doubleToString (MsgDef.Discount, “#.##”) 
     If the value of Discount were 0.04531, the function would return a String object whose value is “0.05”. 
     findString 
     This function searches for a String object within another String object. If the function finds the specified String object, it returns the position of the String&#39;s first character within the other String. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long findString(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String,String) 
                 String to search, String to find 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Long 
                 Position of the String&#39;s first 
                 String is found 
               
               
                   
                 character within the other String 
               
               
                   
                 −1 
                 String is not found 
               
               
                   
               
             
          
         
       
     
     findWord 
     This function searches for a word within a String object. If the function finds the specified word, it returns the position of the word&#39;s first character within the String. The function can only find the word when it is bounded by white space within the String. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long findWord(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String,String) 
                 String to search, word to find 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Long 
                 Position of the Word&#39;s first 
                 Word is found 
               
               
                   
                 character within the String 
               
               
                   
                 −1 
                 Word is not found 
               
               
                   
               
             
          
         
       
     
     foundString 
     This function searches for a String object within another String object and returns a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean foundString(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String,String) 
                 String to search, String to find 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 String is found 
               
               
                   
                 False 
                 String is not found 
               
               
                   
               
             
          
         
       
     
     foundWord 
     This function searches for a word within a String object and returns a Boolean object. The function can only find the word if it is bounded by white space within the String. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean foundWord(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String,String) 
                 String to search, word to find 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 Word is found 
               
               
                   
                 False 
                 Word is not found 
               
               
                   
               
             
          
         
       
     
     getDate 
     This function finds the date in a Calendar object and returns the date as an Integer object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Integer getDate(Calendar) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Calendar) 
                 Calendar to read 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Integer 
                 Resulting Integer, from 1 through 31 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a Calendar object. For another message, the user need the date from the value of DatePurchased in an Integer object. The user would enter the function as follows: 
     GetDate (MsgDef.DatePurchased) 
     If the value of DatePurchased were equivalent to Feb. 13, 2000, the function would return an Integer object whose value is 13. 
     getMonth 
     This function finds the month in a Calendar object and returns the month as an Integer object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Integer getMonth(Calendar) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Calendar) 
                 Calendar to read 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Integer 
                 Resulting Integer, from 1 through 12 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a Calendar object. For another message, the user need the month from the value of DatePurchased in an Integer object. The user would enter the function as follows: 
     getMonth (MsgDef.DatePurchased) 
     If the value of DatePurchased were equivalent to Feb. 13, 2000, the function would return an Integer object whose value is 2. 
     getTokenAt 
     There are two versions of this function. 
     The following function parses a String object into tokens, finds a particular token, and returns the token as a String object. The function assumes that a comma delimits the tokens and lets the user indicate the position of the token to return. 
     If the String to parse contains a null value or the specified token position is out of range, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String getTokenAt(String,Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer) 
                 String to parse, position of the token to find (starting 
               
               
                   
                 with 0) 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Indicated token, or a null value 
               
               
                   
               
             
          
         
       
     
     The following function parses a String object into token, finds a particular token, and returns the token as a String object. The function lets the user specify the character that delimits the tokens and lets the user indicate the position of the token to find. 
     If the String to parse contains a null value or the specified token position is out of range, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String getTokenAt(String,String,Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,String,Integer) 
                 String to parse, delimiter, position of the token 
               
               
                   
                 to find (starting with 0) 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Indicated token, or a null value 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     (1) A message item named Date is defined as a String object that contains a date in the format M/d/yy. For another message, the user need the month from the value of Date in a String object. The user would enter the function as follows: 
     getTokenAt (MsgDef.Date, “/”,  0 ) 
     If Date contained “2/13/00”, the function would return a String object whose value is “2”. 
     (2) A message item named Date is defined as a String object that contains a date in the format MM.dd.yy. For another message, the user need the date from the value of Date in a String object. The user would enter the function as follows: 
     getTokenAt (MsgDef.Date, “/”,  1 ) 
     If Date contained “02.13.00”, the function would return a String object whose value is “13”. 
     (3) A message item named Date is defined as a String object that contains a date in the format M/d/yyyy. For another message, the user need the year from the value of Date in a String object. The user would enter the function as follows: 
     getTokenAtMonth (MsgDef.Date, “/”,  2 ) 
     If Date contained “2/13/2000”, the function would return a String object whose value is “2000”. 
     getYear 
     This function finds the year in a Calendar object and returns the year as an Integer object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Integer getYear(Calendar) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Calendar) 
                 Calendar to read 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Integer 
                 Resulting Integer 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a Calendar object. For another message, the user need the year from the value of DatePurchased in an Integer object. The user would enter the function as follows: 
     getYear (MsgDef.DatePurchased) 
     If the value of DatePurchased were equivalent to Feb. 13, 2000, the function would return an Integer object whose value is 2000. 
     integerToString 
     There are two versions of this function. 
     The following function converts an Integer object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String integerToString(Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Integer) 
                 Integer to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts an Integer object to a String object, using a format mask to format the String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String integerToString(Integer,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Integer,String) 
                 Integer to convert, format mask 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, in the format specified by the mask 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Quantity is defined as an Integer object. For another message, the user need the value of Quantity in a String object, in the format #,###. The user would enter the function as follows: 
     IntegerToString (MsgDef.Quantity, “#,###”) 
     If the value of Quantity were 2500, the function would return a String object whose value is “2,500”. 
     isAlpha 
     This function determines whether all characters in a String object are alphabetic and returns a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean isAlpha(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String) 
                 String to check 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 All characters are alphabetic 
               
               
                   
                 False 
                 Not all character are alphabetic 
               
               
                   
               
             
          
         
       
     
     isAlphaNumeric 
     This function determines whether all characters in a String object are alphanumeric and returns a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean isAlphaNumeric(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String) 
                 String to check 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 All characters are alphanumeric 
               
               
                   
                 False 
                 Not all character are alphanumeric 
               
               
                   
               
             
          
         
       
     
     isNumeric 
     This function determines whether all characters in a String object are numeric and returns a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean isNumeric(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (String) 
                 String to check 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 All characters are numeric 
               
               
                   
                 False 
                 Not all character are numeric 
               
               
                   
               
             
          
         
       
     
     justifyCenter 
     There are two versions of this function. 
     The following function creates a String object of the length indicated by an Integer object and centers a String object within it. If the centered String is shorter than the specified length, the function pads the String on each side with an equal number of spaces. 
     If the centered String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String justifyCenter(String,Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,Integer) 
                 String to center, length of the String to return 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String, or a null value 
               
               
                   
                   
               
             
          
         
       
     
     The following function creates a String object of the length indicated by an Integer object and centers a String object within it. If the centered String is shorter than the specified length, the function pads the String on each side with an equal number of characters specified in another String. 
     If the centered String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String justifyCenter(String,Integer,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer,String) 
                 String to center, length of the String to return, 
               
               
                   
                 and character to use to pad the String 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, or a null value 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Name is defined as a String object. For another message, the user need the value of Name, centered in a String object of length  20 , and padded if necessary with asterisks (*). The user would enter the function as follows: 
     JustifyCenter (MsgDef.Name,  20 , “*”) 
     If the value of Name were “Wolfgang A. Mozart”, the function would return a String object whose value is “*Wolfgang A. Mozart*”. 
     justifyLeft 
     There are two versions of this function. 
     The following function creates a String object of the length indicated by an Integer object and left justifies a String object within it. If the left-justified String is shorter than the specified length, the function pads the String with spaces on the right side. 
     If the left-justified String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String justifyLeft(String,Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer) 
                 String to left justify, length of the String to return 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, or a null value 
               
               
                   
               
             
          
         
       
     
     The following function creates a String object of the length indicated by an Integer object and left justifies a String object within it. If the left-justified String is shorter than the specified length, the function pads the String on the right side with characters specified in another String. 
     If the left justified String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String justifyLeft(String,Integer,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer,String) 
                 String to left justify, length of the String to 
               
               
                   
                 return, and character to use to pad the String 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, or a null value 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Name is defined as a String object. For another message, the user need the value of Name, left justified in a String object of length  20 , and padded if necessary with spaces. The user would enter the function as follows: 
     JustifyLeft (MsgDef.Name,  20 , “*”) 
     If the value of Name were “Franz Shubert”, the function would return a String object whose value is “Franz Shubert”. 
     justifyRight 
     There are two versions of this function. 
     The following function creates a String object of the length indicated by an Integer object and right justifies a String object within it. If the right-justified String is shorter than the specified length, the function pads the String with spaces on the left side. 
     If the right-justified String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String justifyRight(String,Integer) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer) 
                 String to right justify, length of the String to return 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, or a null value 
               
               
                   
               
             
          
         
       
     
     The following function creates a String object of the length indicated by an Integer object and right justifies a String object within it. If the right-justified String is shorter than the specified length, the function pads the String on the left side with characters specified in another String. 
     If the right-justified String is longer than the specified length, the function returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String justifyRight(String,Integer,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,Integer,String) 
                 String to right justify, length of the String to 
               
               
                   
                 return, and character to use to pad the String 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, or a null value 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Name is defined as a String object. For another message, the user need the value of Name, right justified in a String object of length  20 , and padded if necessary with asterisks (*). The user would enter the function as follows: 
     JustifyRight (MsgDef.Name,  20 , “*”) 
     If the value of Name were “Sergei Rachmaninoff”, the function would return a String object whose value is “*Sergei Rachmaninoff”. 
     longToBigDecimal 
     This function converts a Long object to a BigDecimal object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 BigDecimal longToBigDecimal(Long) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Long) 
                 Long to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 BigDecimal 
                 Resulting BigDecimal 
               
               
                   
                   
               
             
          
         
       
     
     longToBoolean 
     This function converts a Long object to a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean longToBoolean(Long) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
                   
               
               
                 (Long) 
                 Long to convert 
               
               
                 Return Type 
                 Value 
                 When 
               
               
                 Boolean 
                 True 
                 Long is any value other than 0 
               
               
                   
                 False 
                 Long is 0 
               
               
                   
               
             
          
         
       
     
     longToDouble 
     This function converts a Long object to a Double object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Double longToDouble(Long) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Long) 
                 Long to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Double 
                 Resulting Double 
               
               
                   
                   
               
             
          
         
       
     
     longToString 
     There are two versions of this function. 
     The following function converts a Long object to a String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String longToString(Long) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (Long) 
                 Long to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a Long object to a String object, using a format mask to format the String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String longToString(Long,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Long,String) 
                 Long to convert, format mask 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String, in the format specified by the mask 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named CustID is defined as a Long object. For another message, the user need the value of CustID in a String object, in the format ##,###. The user would enter the function as follows: 
     longToString (MsgDef.CustID, “##,###”) 
     If the value of CustID were 10321, the function would return a String object whose value is “10,321”. 
     lookup 
     There are two versions of this function. 
     The following function looks up a String object in a lookup table specified in another String object and returns the corresponding value. If the function does not find a corresponding value in the lookup table, it returns a null value. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String lookup(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,String) 
                 String to look up, lookup table 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Value found in the lookup table, or a null value 
               
               
                   
                   
               
             
          
         
       
     
     The following function looks up a String object in a lookup table specified in another String object and returns the corresponding value. If the function does not find a corresponding value in the lookup table, it returns a default value specified in a third String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String lookup(String,String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,String, String) 
                 String to look up, lookup table, default value 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Value found in the lookup table, or the 
               
               
                   
                 default value 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named State is defined as a String object. State always contains a two-letter abbreviation for the name of one of three states in the United States. For another message, the user need the full name of the state in a String object. If no full name corresponds to the abbreviation, the user want the String object to contain “N/A”. The user would enter the function as follows: 
     lookup (MsgDef.State, “MD=Maryland, PA=Pennsylvania, VA=Virginia”, “N/A”) 
     If the value of State were “VA”, the function would return a String object whose value is “Virginia”. 
     lowercase 
     This function converts all characters in a String object to lowercase. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String lowercase(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String 
               
               
                   
                   
               
             
          
         
       
     
     replaceString 
     This function searches a String object for a particular String object, replaces the found String object with a replacement String object, and returns the String object with the replacement String in place. 
     If the function cannot find the String to replace, it returns the String it searched without changing it. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String replaceString(String,String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,String,String) 
                 String to replace, replacement String, String to 
               
               
                   
                 search 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 String with replacement String in place 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Address is defined as a String object. For addresses in the state of Virginia, the value in Address sometimes includes the two-letter abbreviation Va. For another message, the user need a String object that contains the value of Address, but with the full name of the state substituted for the abbreviation. The user would enter the function as follows: 
     replaceString (“VA”, “Virginia, MsgDef.Address) 
     If the value of Address were “Reston, Va. 20191”, the function would return a String object whose value is “Reston, Va. 20191”. 
     replaceWord 
     This function searches a String object for a particular word, replaces the found word with another word, and returns the String object with the replacement word in place. 
     The function can only find the specified word within the String object if the word is: (1) preceded and followed by white space; (2) left justified within the String object and and followed by white space; and (3) right justified within the String object and preceded by white space. If the function cannot find the word, it returns the String it searched without changing it. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String replaceWord(String,String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String,String,String) 
                 Word to replace, replacement word, String to 
               
               
                   
                 search 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 String with replacement word in place 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Address is defined as a String object. For addresses in the state of Maryland, the value in Address sometimes includes the two-letter abbreviation MD. For another message, the user need a String object that contains the value of Address, but with the full name of the state substituted for the abbreviation. The user would enter the function as follows: 
     replaceWord (“MD”, “Maryland”, MsgDef.Address) 
     If the value of Address were “Bethesda, Md. 20904”, the function would return a String object whose value is “Bethesda, Md. 20904”. 
     sizeOf 
     There are two versions of this function. 
     The following function determines the size of a String object and returns the size as a Long object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long sizeOf(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String whose size to determine 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Size of the String 
               
               
                   
                   
               
             
          
         
       
     
     The following function determines the size of a ByteArray object and returns the size as a Long object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long sizeOf(ByteArray) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (ByteArray) 
                 ByteArray whose size to determine 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Size of the ByteArray 
               
               
                   
                   
               
             
          
         
       
     
     stringToBigDecimal 
     This function converts a String object to a Big Decimal object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 BigDecimal stringToBigDecimalString) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 BigDecimal 
                 Resulting BigDecimal 
               
               
                   
                   
               
             
          
         
       
     
     stringToBoolean 
     This function converts a String object to a Boolean object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Boolean stringToBoolean(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Boolean 
                 Resulting Boolean 
               
               
                   
                   
               
             
          
         
       
     
     stringToCalendar 
     There are two versions of this function. 
     The following function converts a String object to a Calendar object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 stringToCalendar(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Calendar 
                 Resulting Calendar 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a String object to a Calendar object, using a format mask to interpret the String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Calendar stringToCalendar(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,String) 
                 String to convert, format mask 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Calendar 
                 Resulting Calendar 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named DatePurchased is defined as a String object that contains a date in the format M/d/yy. For another message, the user need the Calendar equivalent of the value of DatePurchased in a Calendar object. The user would enter the function as follows: 
     stringToCalendar (MsgDef.DatePurchased, “M/d/yy”) 
     If the value of DatePurchased were “2/13/00”, the function would return a Calendar object whose value is the equivalent of Feb. 13, 2000. 
     stringToDouble 
     There are two versions of this function. 
     The following function converts a String object to a Double object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Double stringToDouble(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Double 
                 Resulting Double 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a String object to a Double object, using a format mask to interpret the String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Double stringToDouble(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,String) 
                 String to convert, format mask 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Double 
                 Resulting Double 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named TotalCost is defined as a String object that contains a dollar amount in the format ##,###.##. For another message, the user need the value of TotalCost in a Double object. The user would enter the function as follows: 
     stringToDouble (MsgDef.TotalCost, “##,###.##”) 
     If the value of TotalCost were “5,137.29”, the function would return a Double object whose value is 5137.29. 
     stringToInteger 
     There are two versions of this function. 
     The following function converts a String object to an Integer object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Integer stringToInteger(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Integer 
                 Resulting Integer 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a String object to an Integer object, using a format mask to interpret the String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Integer stringToInteger(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,String) 
                 String to convert, format mask 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Integer 
                 Resulting Integer 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named Quantity is defined as a String object that contains an amount in the format #,###. For another message, the user need the value of Quantity in a String object. The user would enter the function as follows: 
     stringtoInteger (MsgDef.Quantity, “#,###”) 
     If the value of Quantity were “2,500”, the function would return an Integer object whose value is 2500. 
     stringToLong 
     There are two versions of this function. 
     The following function converts a String object to a Long object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long stringToLong(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Resulting Long 
               
               
                   
                   
               
             
          
         
       
     
     The following function converts a String object to a Long object, using a format mask to interpret the String object. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Long stringToLong(String,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String,String) 
                 String to convert, format mask 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 Long 
                 Resulting Long 
               
               
                   
                   
               
             
          
         
       
     
     EXAMPLE 
     A message item named CustID is defined as a String object that contains a number in the format ##,###. For another message, the user need the value of CustID in a Long object. The user would enter the function as follows: 
     stringToLong (MsgDef.CustID, “##,###”) 
     If the value of CustID were “10,321”, the function would return a Long object whose value is 10321. 
     subarray 
     This function finds a ByteArray object within another ByteArray object and returns the found ByteArray object. 
     If the function cannot find the ByteArray, it returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 ByteArray subarray(Long,Long,ByteArray) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Long,Long,ByteArray) 
                 Position of the first byte of the ByteArray to 
               
               
                   
                 find, position of the last byte of the ByteArray 
               
               
                   
                 to find, ByteArray that contains the ByteArray 
               
               
                   
                 to find; positions start with 0; 
               
               
                 Return Type 
                 Value 
               
               
                 ByteArray 
                 ByteArray that has been found 
               
               
                   
               
             
          
         
       
     
     Example A message item named Array is defined as a ByteArray object. For another message, the user need the first eight bytes of Array in a ByteArray object. The user would enter the function as follows: 
     subArray ( 0 ,  7 , MsgDef.Array) 
     substring 
     This function finds a String object within another String object and returns the found String object. 
     If the function cannot find the String, it returns a null value. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String substring(Long,Long,String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (Long,Long,String) 
                 Position of the first character of the String to find, 
               
               
                   
                 position of the last character of the String to find, 
               
               
                   
                 String that contains the String to find 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 String that has been found 
               
               
                   
               
             
          
         
       
     
     trim 
     This function removes white space before and after a String object. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 String trim(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Parameter Type 
                 Value 
               
               
                 (String) 
                 String object from which to remove white space 
               
               
                 Return Type 
                 Value 
               
               
                 String 
                 Resulting String 
               
               
                   
               
             
          
         
       
     
     uppercase 
     This function converts all characters in a String object to uppercase. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 String uppercase(String) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Parameter Type 
                 Value 
               
               
                   
                 (String) 
                 String to convert 
               
               
                   
                 Return Type 
                 Value 
               
               
                   
                 String 
                 Resulting String
In general, in one aspect, the invention provides a modular application collaborator for providing inter-operability between applications including a plurality of connectors for communicating with a like plurality of applications and an interchange server. The interchange server includes an application collaboration module and service module. The service module transfers messages between connectors and the application collaboration module. The application collaboration defines the inter-operability between two or more applications. The interchange server service module includes a transaction service and an error service. Transactions are executed in the application collaboration module and the transaction service records each action and a compensating action for undoing an associated action. An error service monitors for errors in the interchange server, and, upon detection of an error, stops the execution of a transaction and initiates the execution of any required compensating actions to undo the interrupted transaction. The compensating transactions may be executed at the connectors and are not required to be overseen by the interchange server.