Entity relationship and remove operations
strunker Mar 20, 2007 8:02 AMHello,
I have a problem with entity relationships and foreign key constraints. I want to get all child entities deleted when the parent entity is deleted. Therefore I used the CasecadeType.REMOVE, but it doesn't work.
Here is code fragment:
@Entity @Table(name = "Users") public class User implements Serializable { private int id; private List<ChatMessage> sentChatMessages; private List<ChatMessage> receivedChatMessages; @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Column(name = "id", updatable = false, nullable = false) public int getId() { return id; } @OneToMany(mappedBy = "sender", cascade = {CascadeType.REMOVE}, fetch = FetchType.LAZY) public List<ChatMessage> getSentChatMessages() { return this.sentChatMessages; } public void setSentChatMessages(List<ChatMessage> sentChatMessages) { this.sentChatMessages = sentChatMessages; } @OneToMany(mappedBy = "receipient", cascade = {CascadeType.REMOVE}, fetch = FetchType.LAZY) public List<ChatMessage> getReceivedChatMessages() { return this.receivedChatMessages; } public void setReceivedChatMessages(List<ChatMessage> receivedChatMessages) { this.receivedChatMessages = receivedChatMessages; } }
@Entity @Table(name = "ChatMessages") public class ChatMessage implements Serializable { private User sender; private User receipient; private String message; @ManyToOne() @JoinColumn(name = "sender", referencedColumnName = "id", nullable = false) public User getSender() { return this.sender; } public void setSender(User sender) { this.sender = sender; } @ManyToOne() @JoinColumn(name = "receipient", referencedColumnName = "id", nullable = false) public User getReceipient() { return this.receipient; } public void setReceipient(User receipient) { this.receipient = receipient; } }
When I try to delete a user, I exspect that all his messages are also deleted, but this does not happen. Instead I get the following exception:
12:12:43,703 ERROR [JDBCExceptionReporter] ERROR: update or delete on "users" violates foreign key constraint "fk278c74e4eedef195" on "chatmessages"
Detail: Key (id)=(12) is still referenced from table "chatmessages".
12:12:43,703 ERROR [AbstractFlushingEventListener] Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:71)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:249)
at org.hibernate.jdbc.AbstractBatcher.prepareStatement(AbstractBatcher.java:92)
at org.hibernate.jdbc.AbstractBatcher.prepareStatement(AbstractBatcher.java:87)
at org.hibernate.jdbc.AbstractBatcher.prepareBatchStatement(AbstractBatcher.java:218)
at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2414)
at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2632)
at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:73)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:248)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:232)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:144)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338)
at org.hibernate.ejb.AbstractEntityManagerImpl$1.beforeCompletion(AbstractEntityManagerImpl.java:515)
at org.jboss.tm.TransactionImpl.doBeforeCompletion(TransactionImpl.java:1491)
at org.jboss.tm.TransactionImpl.beforePrepare(TransactionImpl.java:1110)
at org.jboss.tm.TransactionImpl.commit(TransactionImpl.java:324)
at org.jboss.tm.TxManager.commit(TxManager.java:240)
at org.jboss.aspects.tx.TxPolicy.endTransaction(TxPolicy.java:175)
at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:87)
at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxInterceptor.java:191)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationInterceptor.java:76)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.stateless.StatelessInstanceInterceptor.invoke(StatelessInstanceInterceptor.java:62)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.aspects.security.AuthenticationInterceptor.invoke(AuthenticationInterceptor.java:77)
at org.jboss.ejb3.security.Ejb3AuthenticationInterceptor.invoke(Ejb3AuthenticationInterceptor.java:102)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagationInterceptor.java:47)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(AsynchronousInterceptor.java:106)
at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:101)
at org.jboss.ejb3.stateless.StatelessContainer.dynamicInvoke(StatelessContainer.java:263)
at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106)
at org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invoke(AOPRemotingInvocationHandler.java:82)
at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:828)
at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:681)
at org.jboss.remoting.transport.socket.ServerThread.processInvocation(ServerThread.java:358)
at org.jboss.remoting.transport.socket.ServerThread.dorun(ServerThread.java:412)
at org.jboss.remoting.transport.socket.ServerThread.run(ServerThread.java:239)
Caused by: java.sql.BatchUpdateException: Batch-Eintrag 0 delete from Users where id=12 wurde abgebrochen. Rufen Sie getNextException auf, um die Ursache zu erfahren.
at org.postgresql.jdbc2.AbstractJdbc2Statement$BatchResultHandler.handleError(AbstractJdbc2Statement.java:2478)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1298)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:347)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeBatch(AbstractJdbc2Statement.java:2540)
at org.jboss.resource.adapter.jdbc.WrappedStatement.executeBatch(WrappedStatement.java:519)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:48)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:242)
... 41 more
What can I do? I tried to remove all user's messages with the entityManager before removing the user, but I had no luck.
I use JBoss 4.0.5 and a Postgres 8.1 database.