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[PersistenceUnit: myJPA] class or package not found
javax.persistence.PersistenceException: [PersistenceUnit: seam22-eclipse-www] Unable to build EntityManagerFactory at$ at java.util.concurrent.ThreadPoolExecutor$Worker.runTask([rt.jar:1.6.0_45] at java.util.concurrent.ThreadPoolExecutor$[rt.jar:1.6.0_45] at[rt.jar:1.6.0_45] at by: javax.persistence.PersistenceException: [PersistenceUnit: seam22-eclipse-www] Unable to build EntityManagerFactory at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory( at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory( at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory( at at$600( at$ ... 4 moreCaused by: org.hibernate.MappingException: Could not instantiate id generator [] at at org.hibernate.mapping.SimpleValue.createIdentifierGenerator( at org.hibernate.internal.SessionFactoryImpl.<init>( at org.hibernate.cfg.Configuration.buildSessionFactory( at org.hibernate.ejb.EntityManagerFactoryImpl.<init>( at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory( ... 9 moreCaused by: java.lang.ClassCastException: cannot be cast to at ... 14 more