The new temporary classloader returned by the WildFly PersistenceUnitInfo.getNewTempClassLoader() is currently created on every call.

Ensure that the cached temp classloader reference is cleared after the PersistenceProvider.createContainerEntityManagerFactory() call returns.

Javadoc description from http://docs.oracle.com/javaee/7/api/javax/persistence/spi/PersistenceUnitInfo.html#getNewTempClassLoader--

ClassLoader getNewTempClassLoader()

Return a new instance of a ClassLoader that the provider may use to temporarily load any classes, resources, or open URLs. The scope and classpath of this loader is exactly the same as that of the loader returned by getClassLoader(). None of the classes loaded by this class loader will be visible to application components. The provider may only use this ClassLoader within the scope of the PersistenceProvider.createContainerEntityManagerFactory(javax.persistence.spi.PersistenceUnitInfo, java.util.Map) call.

Returns:
temporary ClassLoader with same visibility as current loader