[news.eclipse.rt.eclipselink] loader constraint violation

[tbee <tbee@xxxxxxxx>]

What does this exception mean?


java.lang.LinkageError: loader constraint violation: loader (instance of sun/misc/Launcher$AppClassLoader) previously initiated loading for a different type with name "nl/reinders/bm/Batch"
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
	at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
	at nl.reinders.bm.generated.Article.<clinit>(Article.java:248)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:247)
	at org.eclipse.persistence.internal.security.PrivilegedAccessHelper.getClassForName(PrivilegedAccessHelper.java:86)
	at org.eclipse.persistence.descriptors.ClassDescriptor.convertClassNamesToClasses(ClassDescriptor.java:956)
	at org.eclipse.persistence.sessions.Project.convertClassNamesToClasses(Project.java:289)
	at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:200)
	at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.getServerSession(EntityManagerFactoryImpl.java:69)
	at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManagerImpl(EntityManagerFactoryImpl.java:118)
	at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:108)
	at nl.reinders.bm.BM.createEntityManager(BM.java:97)
	at nl.reinders.Reinders$24.actionPerformed(Reinders.java:2855)
	at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
	at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
	at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
	at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
	at javax.swing.AbstractButton.doClick(AbstractButton.java:357)
	at javax.swing.AbstractButton.doClick(AbstractButton.java:337)
	at nl.reinders.Reinders.startJpaScreenSwing(Reinders.java:2911)
	at nl.reinders.Reinders.access$4(Reinders.java:2797)
	at nl.reinders.Reinders$23.run(Reinders.java:2789)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:199)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
	at org.tbee.swing.EventQueue.dispatchEvent(EventQueue.java:83)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:284)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)