Multi thread calls to EntityManagerFactory.getEntityManager() results in
org.apache.openjpa.persistence.ArgumentException
-------------------------------------------------------------------------------------------------------------------------
Key: OPENJPA-739
URL: https://issues.apache.org/jira/browse/OPENJPA-739
Project: OpenJPA
Issue Type: Bug
Affects Versions: 1.1.0
Environment: OS->Windows XP SP2
App Server-> IBM Websphere App Server v6.1.0.13
JDK-> IBM JDK v1.5
JPA-> release 1.1.0
Reporter: Sachin Deshpande
Priority: Critical
Multi thread calls to EntityManagerFactory.getEntityManager() results in
<openjpa-1.1.0-r422266:657916 fatal user error>
org.apache.openjpa.persistence.ArgumentException: Field
"*.*.*.entity.Rtlr.consCollection" declares "*.*.*.entity.Cons.rtlrCd" as its
mapped-by field, but this field is not a direct relation.
at
org.apache.openjpa.jdbc.meta.strats.RelationToManyInverseKeyFieldStrategy.map(RelationToManyInverseKeyFieldStrategy.java:126)
at
org.apache.openjpa.jdbc.meta.strats.RelationCollectionInverseKeyFieldStrategy.map(RelationCollectionInverseKeyFieldStrategy.java:95)
at
org.apache.openjpa.jdbc.meta.FieldMapping.setStrategy(FieldMapping.java:120)
at
org.apache.openjpa.jdbc.meta.RuntimeStrategyInstaller.installStrategy(RuntimeStrategyInstaller.java:80)
at
org.apache.openjpa.jdbc.meta.FieldMapping.resolveMapping(FieldMapping.java:438)
at
org.apache.openjpa.jdbc.meta.FieldMapping.resolve(FieldMapping.java:403)
at
org.apache.openjpa.jdbc.meta.ClassMapping.resolveMapping(ClassMapping.java:812)
at
org.apache.openjpa.meta.ClassMetaData.resolve(ClassMetaData.java:1625)
at
org.apache.openjpa.meta.MetaDataRepository.processBuffer(MetaDataRepository.java:717)
at
org.apache.openjpa.meta.MetaDataRepository.resolveMapping(MetaDataRepository.java:677)
at
org.apache.openjpa.meta.MetaDataRepository.resolve(MetaDataRepository.java:555)
at
org.apache.openjpa.meta.MetaDataRepository.getMetaData(MetaDataRepository.java:308)
at org.apache.openjpa.enhance.PCEnhancer.<init>(PCEnhancer.java:248)
at org.apache.openjpa.enhance.PCEnhancer.<init>(PCEnhancer.java:219)
at org.apache.openjpa.enhance.PCEnhancer.<init>(PCEnhancer.java:187)
at
org.apache.openjpa.enhance.ManagedClassSubclasser.prepareUnenhancedClasses(ManagedClassSubclasser.java:121)
at
org.apache.openjpa.kernel.AbstractBrokerFactory.loadPersistentTypes(AbstractBrokerFactory.java:310)
at
org.apache.openjpa.kernel.AbstractBrokerFactory.initializeBroker(AbstractBrokerFactory.java:228)
at
org.apache.openjpa.kernel.AbstractBrokerFactory.newBroker(AbstractBrokerFactory.java:190)
at
org.apache.openjpa.kernel.DelegatingBrokerFactory.newBroker(DelegatingBrokerFactory.java:142)
at
org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:192)
at
org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:145)
at
org.apache.openjpa.persistence.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:56)
at *.*.*.utility.DBUtilities.getEntityManager(DBUtilities.java:20)
...
...
...
To access all EntityManagers we have the following custom class:
public class DBUtilities {
private static EntityManagerFactory emf = null;
static {
CommonResources resource = CommonResources.getInstance();
String env = resource.getValue("jndi.persistanceUnit.use");
emf = Persistence.createEntityManagerFactory(env);
}
/**
* Return Entity Manager
* @return
*/
public static EntityManager getEntityManager() {
return emf.createEntityManager();
}
}
The code is supposed to run in a multi-threaded environment where
parallel threads invoke DBUtilities.getEntityManager() method. In such a
scenario, we get the above exception.
However, if we 'synchronize' the DBUtilities's getEntityManager() method,
the exception does not occur and the code executes successfully.
This is contrary to our understanding that EntityManagerFactory is thread
safe and EntityManagerFactory's .createEntityManager() method creates a new
instance of EntityManager everytime though being invoked by multiple threads.
Please advice.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
