Dusk vs Dawn. Dusk and dawn are actually opposite times of the day. The former refers to the time before night starts while the latter refers to the time just before the night ends. There is no specific time for them, however, as sunrise and sunset occurs differently everyday. Dusk.
What is JMS? Java Message Service (JMS) is an application program interface (API) from Sun Microsystems that supports the messaging communication between computers / applications / software components in a network.
jms handles publish/subscribe, which is a bit more complicated that the point-to-point example you gave. you are not tied to a specific implementation, and can swap it out if your needs change in the future, w/out messing w/ your java code.MS is an API used to transfer messages between two or more clients. It's specs are defined under JSR 914. JMS are just kind of interfaces/APIs and the concrete classes must be implemented. These are already implemented by various organizations/Providers. they are called JMS providers.