title: GAE: Access denied exception causing error on persistence provider
body: <p>I just upgraded to GAE SDK 1.7.1 and now I'm trying to use JPA 2 in my [former] functioning project.
  When I try to use the Entity Manager it throws the following exception:</p>
  
  <pre><code>java.lang.ExceptionInInitializerError
      at java.lang.Class.forName0(Native Method)
      at java.lang.Class.forName(Class.java:169)
      at com.google.appengine.tools.development.agent.runtime.RuntimeHelper.checkRestricted(RuntimeHelper.java:69)
      at com.google.appengine.tools.development.agent.runtime.Runtime.checkRestricted(Runtime.java:64)
      at com.olympya.futweb.ServicesServlet.doPost(ServicesServlet.java:39)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
      at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
      at com.google.appengine.tools.appstats.AppstatsFilter.doFilter(AppstatsFilter.java:141)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97)
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
      at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
      at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
      at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
      at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
      at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
      at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:94)
      at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
      at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:370)
      at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
      at org.mortbay.jetty.Server.handle(Server.java:326)
      at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
      at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
      at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
      at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
      at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
      at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
      at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
  Caused by: javax.persistence.PersistenceException: Explicit persistence provider error(s) occurred for "transactions-optional" after trying the following discovered implementations: org.datanucleus.api.jpa.PersistenceProviderImpl from provider: org.datanucleus.api.jpa.PersistenceProviderImpl
      at javax.persistence.Persistence.createPersistenceException(Persistence.java:242)
      at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:184)
      at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:70)
      at com.olympya.futweb.datamodel.EMHelper.&lt;clinit&gt;(EMHelper.java:49)
      ... 38 more
  Caused by: org.datanucleus.exceptions.NucleusUserException: Errors were encountered when loading the MetaData for the persistence-unit "transactions-optional". See the nested exceptions for details
      at org.datanucleus.metadata.MetaDataManager.loadPersistenceUnit(MetaDataManager.java:979)
      at org.datanucleus.api.jpa.JPAEntityManagerFactory.initialiseNucleusContext(JPAEntityManagerFactory.java:754)
      at org.datanucleus.api.jpa.JPAEntityManagerFactory.initialise(JPAEntityManagerFactory.java:417)
      at org.datanucleus.api.jpa.JPAEntityManagerFactory.&lt;init&gt;(JPAEntityManagerFactory.java:380)
      at org.datanucleus.api.jpa.PersistenceProviderImpl.createEntityManagerFactory(PersistenceProviderImpl.java:91)
      at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:150)
      ... 40 more
  Caused by: java.security.AccessControlException: access denied (java.lang.RuntimePermission accessClassInPackage.sun.reflect.generics.reflectiveObjects)
      at java.security.AccessControlContext.checkPermission(AccessControlContext.java:374)
      at java.security.AccessController.checkPermission(AccessController.java:546)
      at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
      at com.google.appengine.tools.development.DevAppServerFactory$CustomSecurityManager.checkPermission(DevAppServerFactory.java:283)
      at java.lang.SecurityManager.checkPackageAccess(SecurityManager.java:1512)
      at java.lang.ClassLoader$1.run(ClassLoader.java:330)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.lang.ClassLoader.checkPackageAccess(ClassLoader.java:328)
      at java.lang.Class.getDeclaredMethods0(Native Method)
      at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
      at java.lang.Class.getDeclaredMethods(Class.java:1791)
      at org.datanucleus.metadata.annotations.AbstractAnnotationReader.getJavaBeanAccessorAnnotationsForClass(AbstractAnnotationReader.java:310)
      at org.datanucleus.metadata.annotations.AbstractAnnotationReader.getMetaDataForClass(AbstractAnnotationReader.java:146)
      at org.datanucleus.metadata.annotations.AnnotationManagerImpl.getMetaDataForClass(AnnotationManagerImpl.java:171)
      at org.datanucleus.metadata.MetaDataManager.loadAnnotationsForClass(MetaDataManager.java:2650)
      at org.datanucleus.metadata.MetaDataManager.loadPersistenceUnit(MetaDataManager.java:955)
      ... 45 more
  </code></pre>
  
  <p>My persistence.xml is this:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8" ?&gt;
  &lt;persistence xmlns="http://java.sun.com/xml/ns/persistence"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
          http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0"&gt;
  
      &lt;persistence-unit name="transactions-optional"&gt;
          &lt;provider&gt;org.datanucleus.api.jpa.PersistenceProviderImpl&lt;/provider&gt;
          &lt;properties&gt;
              &lt;property name="datanucleus.NontransactionalRead" value="true"/&gt;
              &lt;property name="datanucleus.NontransactionalWrite" value="true"/&gt;
              &lt;property name="datanucleus.ConnectionURL" value="appengine"/&gt;
              &lt;property name="datanucleus.appengine.multipleRelationsOfSameTypeAreErrors" value="false"/&gt;
              &lt;property name="datanucleus.DetachAllOnCommit" value="false"/&gt;
              &lt;property name="datanucleus.DetachOnClose" value="true"/&gt;
              &lt;property name="datanucleus.appengine.datastoreEnableXGTransactions" value="true"/&gt;
          &lt;/properties&gt;
      &lt;/persistence-unit&gt; 
  
  &lt;/persistence&gt;
  </code></pre>
  
  <p>My helper is this:</p>
  
  <pre><code>    public final class EMHelper
  {
      private static final EMHelper emhInstance = new EMHelper();
      private static final EntityManagerFactory emfInstance = 
              Persistence.createEntityManagerFactory("transactions-optional");
  
      private EMHelper()
      {
      }
  
      public static EMHelper getInstance()
      {
          return emhInstance;
      }
  
      public static EntityManager getEntityManager()
      {
          return emfInstance.createEntityManager();
      }
          ...
  </code></pre>