Hibernate：org.hibernate.AssertionFailure：com.xxx.Bean条目中的null id

Question

I was faced to the following error:

com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract void com.xxx.Service.save(com.xxx.Bean)' threw an unexpected exception: org.hibernate.AssertionFailure: null id in com.xxx.Bean entry (don't flush the Session after an exception occurs)
    at com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:385)
    at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:588)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:208)
    at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:248)
    at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:306)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:383)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:243)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:288)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:680)
Caused by: org.hibernate.AssertionFailure: null id in com.xxx.Bean entry (don't flush the Session after an exception occurs)
    at org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:82)
    at org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:190)
    at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:147)
    at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:219)
    at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:99)
    at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
    at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
    at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383)
    at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133)
    at com.xxx.ServiceImpl.save(ServiceImpl.java:32)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    ... 23 more

Here is MySQL table definition:

CREATE TABLE `tblARF` (
  `ARF_ID` bigint(19) NOT NULL AUTO_INCREMENT,
  `ARF_MANUFACTURER_MNF_ID` bigint(19) NOT NULL,
  ...
  PRIMARY KEY (`ARF_ID`),
  KEY `ARF_MANUFACTURER_MNF_ID` (`ARF_MANUFACTURER_MNF_ID`)
)

And here is Hibernate mapping:

<class name="Bean" table="tblARF">
  <id name="key" type="long" unsaved-value="null">
    <column name="ARF_ID" not-null="true"/>
    <generator class="identity" />
  </id>
<many-to-one column="ARF_MANUFACTURER_MNF_ID" name="manufacturer"
    class="ManufacturerBean" not-null="true" lazy="false"/>
...
</class>

Java code:

Session s = hibernate.getCurrentSession();
Transaction t = s.beginTransaction();
s.merge(bean.getManufacturer());
s.save(bean);
t.commit();

I noticed that if I remove KEY ARF_MANUFACTURER_MNF_ID (ARF_MANUFACTURER_MNF_ID) than AssertionFailure doesn't happen. Is there a way to avoid this error without removing the KEY?

This solution doesn't work for me unfortunately.

Answer 1

The answer was found here: https://forum.hibernate.org/viewtopic.php?f=1&t=1009141

'order' is a reserved keyword in SQL so if you want to use if as a column name it needs to be quoted. See http://docs.jboss.org/hibernate/core/3.6/reference/en-US/html/mapping.html#mapping-quotedidentifiers for instructions how to enabled this.

Answer 2

The Exception you have posted said what the problem is:

Caused by: org.hibernate.AssertionFailure: null id in com.xxx.Bean entry (don't flush the Session after an exception occurs)

In Hibernate you have to throw away the Hibernate Session after a Session related Exception occures.

But I guess that is not your question.

You need to set the ID of your Bean or use <generator class="native" /> ( @GeneratedValue(strategy=GenerationType.AUTO) ) instead.

Added try to replace: merge by save

Answer 3

Sometimes the real error lies somewhere else. To check the exact error use Debug mode and make use of printstacktrace() method of exception. It gives you the more detailed reason. In my case I had used String where the column was of type int.

Answer 4

I'm not sure whether it's related to your problem, but note the wrong usage of merge() .

merge() doesn't make the object passed into it persistent, it returns another instance with the same state instead, so you should write

bean.setManufacturer(s.merge(bean.getManufacturer()));