Mapping a class more than once using entity names causes NullPointerException in org.hibernate.ejb.event.EJB3FlushEntityEventListener ------------------------------------------------------------------------------------------------------------------------------------- Key: HHH-4967 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-4967 Project: Hibernate Core Issue Type: Bug Components: entity-manager Affects Versions: 3.3.2 Environment: Hibernate Entity Manager 3.3.2.GA, JBoss EAP 4.3, Oracle 10 Reporter: Gunnar von der Beck Attachments: hibernate-HHH-4967.zip Original Estimate: 30 minutes Remaining Estimate: 30 minutes Map a class more than once and use *entity names*, e.g. as follows: {code:xml} <?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <!-- Mapping for multilingual texts up to 4000 characters --> <class dynamic-insert="true" dynamic-update="true" optimistic-lock="version" name="mypackage.MultilingualText" table="multilingualtext" entity-name="MultilingualShort"> ... <!-- the short text --> <property name="text" type="java.lang.String"> <column name="text" sql-type="varchar2(4000)" /> </property> </class> <!-- Mapping for multilingual texts holding more than 4000 characters --> <class dynamic-insert="true" dynamic-update="true" optimistic-lock="version" name="mypackage.MultilingualText" table="multilinguallongtext" entity-name="MultilingualLong"> ... <!-- the long text --> <property name="text" type="java.lang.String"> <column name="text" sql-type="clob" /> </property> </class> </hibernate-mapping> {code} Use this entity names within a list / set / map /... as follows: {code:xml} <class name="myClass" ...> ... <!-- multilingual text field for up to 4000 characters --> <set access="field" cascade="all,delete-orphan" fetch="join" lazy="false" name="description" table="myclassdescription"> <key> <column name="myclass_id" sql-type="varchar2(36)" /> </key> <many-to-many unique="true" class="mypackage.MultilingualText" entity-name="MultilingualShort"> <column name="text_id" sql-type="varchar2(36)"/> </many-to-many> </set> ... </class> {code} When modifying such a list / set / map and calling {{entityManager.merge(<myClass>)}} you get the following exception on {{entityManager.flush()}}: {noformat} java.lang.NullPointerException at org.hibernate.ejb.event.EJB3FlushEntityEventListener.copyState(EJB3FlushEntityEventListener.java:53) at org.hibernate.ejb.event.EJB3FlushEntityEventListener.invokeInterceptor(EJB3FlushEntityEventListener.java:42) at org.hibernate.event.def.DefaultFlushEntityEventListener.handleInterception(DefaultFlushEntityEventListener.java:308) at org.hibernate.event.def.DefaultFlushEntityEventListener.scheduleUpdate(DefaultFlushEntityEventListener.java:248) at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:128) at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:196) at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:76) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:26) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000) at org.hibernate.ejb.AbstractEntityManagerImpl.flush(AbstractEntityManagerImpl.java:304) {noformat} *Solution:* correct the {{org.hibernate.ejb.event.EJB3FlushEntityEventListener}} as follows: {code:title=EJB3FlushEntityEventListener.java|borderStyle=solid} /** * Overrides the LifeCycle OnSave call to call the PreUpdate operation. * <p> * Error corrected version derived from {@code hibernate-entitymanager-3.3.2GA}. * See method {@code copyState}: considered entity name! */ public class EJB3FlushEntityEventListener extends DefaultFlushEntityEventListener implements CallbackHandlerConsumer { /** * This class serial version UID. */ private static final long serialVersionUID = 1L; private EntityCallbackHandler callbackHandler; public void setCallbackHandler(EntityCallbackHandler callbackHandler) { this.callbackHandler = callbackHandler; } public EJB3FlushEntityEventListener() { super(); } public EJB3FlushEntityEventListener(EntityCallbackHandler callbackHandler) { super(); this.callbackHandler = callbackHandler; } @Override protected boolean invokeInterceptor( SessionImplementor session, Object entity, EntityEntry entry, Object[] values, EntityPersister persister ) { boolean isDirty = false; if ( entry.getStatus() != Status.DELETED ) { if ( callbackHandler.preUpdate( entity ) ) { isDirty = copyState( entity, entry.getEntityName() ,persister.getPropertyTypes(), values, session.getFactory() ); } } return super.invokeInterceptor( session, entity, entry, values, persister ) || isDirty; } /** * copy the entity state into the state array and return true if the state has changed */ // modified parameter list: ++entityName private boolean copyState(Object entity, String entityName, Type[] types, Object[] state, SessionFactory sf) { // modified: consider entity names when resolving metadata! ClassMetadata metadata = (entityName != null ? sf.getClassMetadata(entityName) : sf.getClassMetadata(entity.getClass())); Object[] newState = metadata.getPropertyValues( entity, EntityMode.POJO ); int size = newState.length; boolean isDirty = false; for ( int index = 0; index < size ; index++ ) { if ( !types[index].isEqual( state[index], newState[index], EntityMode.POJO ) ) { isDirty = true; state[index] = newState[index]; } } return isDirty; } } {code} The significant change of the code is to consider the entity name when looking up {{ClassMetadata}} in method {{copyState()}}: {code} ClassMetadata metadata = (entityName != null ? sf.getClassMetadata(entityName) : sf.getClassMetadata(entity.getClass())); {code}