Getting org.hibernate.DuplicateMappingException: Duplicate entity mapping in EAP 7.0.0 Beta

Issue

• We are upgrading from EAP 5 to EAP 7 (via EAP 6). It worked in EAP 6 but is not working in EAP 7. It seems like a Hibernate 5 issue. We are not sure what is causing hibernate to read the mapping files twice. The duplicate mapping is not specific to a particular class, it can happen to any class.

• We are is getting the below error:

2016-01-08 11:17:42,648 ERROR [org.jboss.msc.service.fail] (ServerService Thread Pool -- 75) MSC000001: Failed to start service jboss.persistenceunit : org.jboss.msc.service.StartException in service jboss.persistenceunit."Test": org.hibernate.DuplicateMappingException: Duplicate entity mapping
    at org.jboss.as.jpa.service.PersistenceUnitServiceImpl$1$1.run(PersistenceUnitServiceImpl.java:172)
    at org.jboss.as.jpa.service.PersistenceUnitServiceImpl$1$1.run(PersistenceUnitServiceImpl.java:117)
    at org.wildfly.security.manager.WildFlySecurityManager.doChecked(WildFlySecurityManager.java:667)
    at org.jboss.as.jpa.service.PersistenceUnitServiceImpl$1.run(PersistenceUnitServiceImpl.java:182)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
    at org.jboss.threads.JBossThread.run(JBossThread.java:320)
Caused by: org.hibernate.DuplicateMappingException: Duplicate entity mapping
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.addEntityBinding(InFlightMetadataCollectorImpl.java:271)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindDiscriminatorSubclassEntities(ModelBinder.java:512)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindDiscriminatorSubclassEntity(ModelBinder.java:560)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindDiscriminatorSubclassEntities(ModelBinder.java:510)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindDiscriminatorSubclassEntity(ModelBinder.java:560)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindDiscriminatorSubclassEntities(ModelBinder.java:510)
    at org.hibernate.boot.model.source.internal.hbm.ModelBinder.bindEntityHierarchy(ModelBinder.java:197)
    at org.hibernate.boot.model.source.internal.hbm.HbmMetadataSourceProcessorImpl.processEntityHierarchies(HbmMetadataSourceProcessorImpl.java:144)
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess$1.processEntityHierarchies(MetadataBuildingProcess.java:218)
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:265)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:770)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:797)
    at org.jboss.as.jpa.hibernate5.TwoPhaseBootstrapImpl.build(TwoPhaseBootstrapImpl.java:44)
    at org.jboss.as.jpa.service.PersistenceUnitServiceImpl$1$1.run(PersistenceUnitServiceImpl.java:154)
    ... 7 more