EntityManager.remove() throws java.lang.IllegalArgumentException: Removing a detached instance ?

[aupres]

@Stateless

public class LoginSession implements ILoginSession {

@PersistenceContext(unitName="MyHome")

EntityManager em;

....

public Object loginFunc(Class clazz, Object primaryKey) {
  // TODO Auto-generated method stub
  return em.find(clazz, primaryKey);
}

public Object removeFunc(Serializable entity) {
  // TODO Auto-generated method stub
  em.remove(entity);
  return entity;
}

.....

}

bean codes are like above.

in JSP file

ILoginSession login = ctx.lookup(LoginSession/remote);

Members erase = (Members)login.loginFunc(Members.class,"father");
out.println(erase.toString()); // It works to this lines

login.removeFunc(erase); // but this line thows Exception

EntityManager.remove() fuction throws "java.lang.IllegalArgumentException: Removing a detached instance"

I need your advice..

Best Regards....^_^

[philani]

try calling merge(). You entity is not being managed by EntityManager anymore.

[iabughosh]

thats right, or you can find the entity by primary key then remove it like this :

YourEntity e = em.find(YourEntity.class, entityId);//e is the managed entity

em.remove(e);

[aupres]

Thanks, guys!

It works!!! ^_^