glassfish - Javassist ClassCastException in Hibernate and Netbeans -

could me this, have happened making application generate error. following tutorial on using hibernate in netbeans. after getting line "from film", according tutorial executed test read records of film table result error below. googled find do, have seen far it's reported javassist jar file existing in different directories. one, in hibernate (hibernate 4.x-javassist-3.15.0.ga) directory, found out true, , other in glassfish (glassfish server 4) directory. tried searching in glassfish lib directory, nothing seems exist.

java.lang.classcastexception: dvdstore.language_$$_javassist_4 cannot cast javassist.util.proxy.proxyobject     @ org.hibernate.proxy.pojo.javassist.javassistlazyinitializer.getproxy(javassistlazyinitializer.java:147)     @ org.hibernate.proxy.pojo.javassist.javassistproxyfactory.getproxy(javassistproxyfactory.java:71)     @ org.hibernate.tuple.entity.abstractentitytuplizer.createproxy(abstractentitytuplizer.java:631)     @ org.hibernate.persister.entity.abstractentitypersister.createproxy(abstractentitypersister.java:3737)     @ org.hibernate.event.def.defaultloadeventlistener.createproxyifnecessary(defaultloadeventlistener.java:360)     @ org.hibernate.event.def.defaultloadeventlistener.proxyorload(defaultloadeventlistener.java:281)     @ org.hibernate.event.def.defaultloadeventlistener.onload(defaultloadeventlistener.java:152)     @ org.hibernate.impl.sessionimpl.fireload(sessionimpl.java:1090)     @ org.hibernate.impl.sessionimpl.internalload(sessionimpl.java:1038)     @ org.hibernate.type.entitytype.resolveidentifier(entitytype.java:630)     @ org.hibernate.type.entitytype.resolve(entitytype.java:438)     @ org.hibernate.engine.twophaseload.initializeentity(twophaseload.java:139)     @ org.hibernate.loader.loader.initializeentitiesandcollections(loader.java:982)     @ org.hibernate.loader.loader.doquery(loader.java:857)     @ org.hibernate.loader.loader.doqueryandinitializenonlazycollections(loader.java:274)     @ org.hibernate.loader.loader.dolist(loader.java:2542)     @ org.hibernate.loader.loader.listignorequerycache(loader.java:2276)     @ org.hibernate.loader.loader.list(loader.java:2271)     @ org.hibernate.hql.classic.querytranslatorimpl.list(querytranslatorimpl.java:940)     @ org.hibernate.engine.query.hqlqueryplan.performlist(hqlqueryplan.java:196)     @ org.hibernate.impl.sessionimpl.list(sessionimpl.java:1268)     @ org.hibernate.impl.queryimpl.list(queryimpl.java:102) 

the list jars project.

you using old version of javassist. hibernate 4, require javassist version newer 3.16. same issue discussed in this related question. consider using build tool maven or gradle build project. these tools take care of resolving transitive dependencies such can avoid such version conflicts.