EntityManagerFactory emf = Persistence.createEntityManagerFactory("org.eclipse.jubula");
EntityManager em = emf.createEntityManager();

Caused by: javax.persistence.PersistenceException: No Persistence provider for EntityManager named org.eclipse.jubula
	at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
	at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
	at jpatest.Activator.start(Activator.java:37)
	at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:711)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:702)
	... 63 more

        List<DbLockPO> locks  = null;
        List<ITestDataCategoryPO> cats = null;
        List<INodePO> nodes = null;
     
		try {
			locks = em.createQuery("select lock from DbLockPO as lock").getResultList();
		       	
		    for (DbLockPO dbLockPo : locks) {
				
					System.out.println("got item: "+dbLockPo.getPoId());
					Query queryCats = em.createQuery("select cat from TestDataCategoryPO cat where cat.id = :catId", ITestDataCategoryPO.class);
					queryCats.setParameter("catId", dbLockPo.getPoId());	            		
					cats= queryCats.getResultList();  
				        		 
				for (ITestDataCategoryPO catPO : cats) {
			
					Query queryNodes = em.createQuery("select node from NodePO node where node.id = :nodeId", INodePO.class);
					queryNodes.setParameter("nodeId", catPO.getParentProjectId());
					nodes = queryNodes.getResultList();
					
					for (INodePO iNodePO : nodes) {
						System.out.println("Locked Dataset belong to: "+iNodePO.getName());
					}
				}
			}
		}
        catch(Exception e){
        	e.printStackTrace();
        }

                Persistor.setDbConnectionName(new DatabaseConnectionInfo(){			
			public String getDriverClassName(){ ...	}

			public String getConnectionUrl() {...}});
		
		Persistor.setPw("password");
		Persistor.setUser("username");
		Persistor.setUrl("jdbc:mysql://server:3306/dbname");
		
		Persistor.init();
		EntityManager em = org.eclipse.jubula.client.core.persistence.Persistor.instance().openSession();
		

	List<DatabaseConnection> availableConns = DatabaseConnectionConverter.computeAvailableConnections();
		
		for (DatabaseConnection databaseConnection : availableConns) {
			System.out.println(databaseConnection.getConnectionInfo().getConnectionUrl());
			System.out.println(databaseConnection.getConnectionInfo().getProperty(PersistenceUnitProperties.JDBC_URL));
			System.out.println(databaseConnection.getConnectionInfo().getProperty(PersistenceUnitProperties.JDBC_PASSWORD));
			System.out.println();
		}