hello to all,
i am developing my first JPA application on IBM Rational Application Developer 7.5.5, windows vista business, and using websphere application server 7.0 .
using RAD , i created a JPA application and i created my entities and entity managers as well successfully, then for trying to actually manipulate my data, i created a Deneme.java which has the code

Java Code: 
 
package source;
import entities.controller.*;
import entities.*;
import javax.persistence.*;
public class Deneme {
 
 public static void main(String[] args) {
 
  EntityManager em = Persistence.createEntityManagerFactory("Dene").createEntityManager();
  System.out.print("success");
 }
}
and i made the application run as java application but it gave the following error :
------------------------------------------
Exception in thread "main" java.lang.NoClassDefFoundError: org.apache.commons.collections.set.MapBackedSet
at org.apache.openjpa.lib.util.concurrent.ConcurrentR eferenceHashSet.<init>(ConcurrentReferenceHashSet. java:68)
at org.apache.openjpa.kernel.AbstractBrokerFactory.ne wBrokerSet(AbstractBrokerFactory.java:486)
at org.apache.openjpa.kernel.AbstractBrokerFactory.<i nit>(AbstractBrokerFactory.java:148)
at org.apache.openjpa.jdbc.kernel.JDBCBrokerFactory.< init>(JDBCBrokerFactory.java:87)
at com.ibm.ws.persistence.jdbc.kernel.WsJpaJDBCBroker Factory.<init>(WsJpaJDBCBrokerFactory.java:77)
at com.ibm.ws.persistence.jdbc.kernel.WsJpaJDBCBroker Factory.newInstance(WsJpaJDBCBrokerFactory.java:12 2)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Native MethodAccessorImpl.java:48)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(De legatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:600)
at org.apache.openjpa.kernel.Bootstrap.invokeFactory( Bootstrap.java:124)
at org.apache.openjpa.kernel.Bootstrap.newBrokerFacto ry(Bootstrap.java:62)
at org.apache.openjpa.persistence.PersistenceProvider Impl.getBrokerFactory(PersistenceProviderImpl.java :102)
at org.apache.openjpa.persistence.PersistenceProvider Impl.createEntityManagerFactory(PersistenceProvide rImpl.java:81)
at com.ibm.websphere.persistence.PersistenceProviderI mpl.createEntityManagerFactory(PersistenceProvider Impl.java:71)
at com.ibm.websphere.persistence.PersistenceProviderI mpl.createEntityManagerFactory(PersistenceProvider Impl.java:41)
at org.apache.openjpa.persistence.PersistenceProvider Impl.createEntityManagerFactory(PersistenceProvide rImpl.java:109)
at org.apache.openjpa.persistence.PersistenceProvider Impl.createEntityManagerFactory(PersistenceProvide rImpl.java:53)
at javax.persistence.Persistence.createFactory(Persis tence.java:172)
at javax.persistence.Persistence.createEntityManagerF actory(Persistence.java:112)
at javax.persistence.Persistence.createEntityManagerF actory(Persistence.java:66)
at source.Deneme.main(Deneme.java:20)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.collections.set.MapBackedSet
at java.net.URLClassLoader.findClass(URLClassLoader.j ava:421)
at java.lang.ClassLoader.loadClass(ClassLoader.java:6 43)
at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:346)
at java.lang.ClassLoader.loadClass(ClassLoader.java:6 09)
... 22 more
--------------------------------------------------
using the first line of the exception i made asearch on google and i found the suggestion on this forum post and copied commons collections, beanutils, digester, logging and openjpa latest zip file to the build path of my application.
and i made the aplication run. but still i get the very same error :(
if it will make any help here is also the persistence.xml contents
Java Code: 
 
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="[URL="http://java.sun.com/xml/ns/persistence"]Java Persistence API: XML Schemas[/URL]" xmlns:xsi="[URL]http://www.w3.org/2001/XMLSchema-instance[/URL]" xsi:schemaLocation="[URL="http://java.sun.com/xml/ns/persistence"]Java Persistence API: XML Schemas[/URL] [URL]http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd[/URL]">
<persistence-unit name="Dene">
<jta-data-source>jdbc/DeneJPA</jta-data-source>
<class>entities.Child</class>
<class>entities.Parent</class>
<properties>
<property name="openjpa.jdbc.Schema" value="Schema"/>
</properties>
</persistence-unit>
</persistence>
can anyone please suggest me how to come over of this problem ?
thank you