Hi, I am getting exception in the following line of code. userData = (em.createQuery("select u from Users u where u.email= ?1").setParameter(1, &quot;mail(a)mailid.com&quot;)).getResultList(); userData : is a List object, em : is a EntityManager object Users : is a table Exception Message ============ Exception caught is : <4|true|0.9.7> org.apache.openjpa.persistence.ArgumentException: Could not locate metadata for the class using alias "Users". Persistent.xml ========= <persistence-unit name="userDatabase" transaction-type="RESOURCE_LOCAL"> org.apache.openjpa.persistence.PersistenceProviderImpl <exclude-unlisted-classes>false</exclude-unlisted-classes> </persistence-unit> Please let me know if someone had already faced this issue and found a resolution for it. - Kumanan View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4086460#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...