WEB9031 - cannot store entity with sequence generated id - jpa

Question

I am using glassfish, postgres and openjpa.
I only have one bean and first want to create a new intance and store it in DB. I created a new User-Object, filled it (except the id) and got - trying to persist - following exception:
Caused by: java.lang.IllegalStateException: WEB9031: WebappClassLoader unable to load resource [org.apache.openjpa.util.LongId], because it has not yet been started, or was already stopped
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1401)
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1359)
at org.myPlace.server.user.UserPDO.pcNewObjectIdInstance(UserPDO.java)
at org.apache.openjpa.enhance.PCRegistry.newObjectId(PCRegistry.java:142)
at org.apache.openjpa.meta.MetaDataRepository.processRegisteredClass(MetaDataRepository.java:1694)
at org.apache.openjpa.meta.MetaDataRepository.processRegisteredClasses(MetaDataRepository.java:1644)
... 128 more
WARNING: StandardWrapperValve[Faces Servlet]: PWC1406: Servlet.service() for
servlet Faces Servlet threw exception
java.lang.IllegalStateException: WEB9031: WebappClassLoader unable to load resource
[org.apache.openjpa.util.LongId], because it has not yet been started, or was already stopped
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1401)
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1359)
at org.myPlace.server.user.UserPDO.pcNewObjectIdInstance(UserPDO.java)
at org.apache.openjpa.enhance.PCRegistry.newObjectId(PCRegistry.java:142)
at org.apache.openjpa.meta.MetaDataRepository.processRegisteredClass(MetaDataRepository.java:1694)
My bean looks like this:
#Entity
#Table(name="tbl_User")
public class UserPDO implements Serializable {
private long id;
private String username;
private String password;
public UserPDO() {}
#Id
#GeneratedValue(strategy=GenerationType.SEQUENCE, generator="user_seq_gen")
#SequenceGenerator(name="user_seq_gen", sequenceName="user_seq")
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
... }
My persistence.xml looks like this:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="myPlace" transaction-type="JTA">
<provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
<class>org.myPlace.server.user.UserPDO</class>
<properties>
<property name="openjpa.jdbc.DBDictionary" value="postgres"/>
<property name="openjpa.ConnectionDriverName" value="org.postgresql.Driver"/>
<property name="openjpa.ConnectionURL" value="jdbc:postgresql://localhost:5432/myPlace"/>
<property name="openjpa.ConnectionPassword" value="myPlace"/>
<property name="openjpa.ConnectionUserName" value="myPlace"/>
<property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema"/>
<property name="openjpa.Log" value="File=/home/username/apache.log, DefaultLevel=ERROR, Tool=INFO, SQL=TRACE"/>
<property name="openjpa.DynamicEnhancementAgent" value="false" />
<property name="openjpa.RuntimeUnenhancedClasses" value="unsupported" />
<property name="openjpa.DataCache" value="false"/>
<property name="openjpa.QueryCache" value="false"/>
</properties>
</persistence-unit>
The table is created correctly, so is the sequence. But when I want to create a new user object via
public <T> T create(T t) {
this.em.persist(t);
this.em.flush();
this.em.refresh(t);
return t;
}
I get the exception mentioned above. I found some questions/answers here that suggest that deactiving runtime-enhancement should do the trick. But it didn't work for me. My first idea was, that it might be a Classloader-Leak. I copied postgres-driver and openjpa-jars into the glassfish/lib-folder.
Can anybody help? Thanks!