anonymous wrote : | i will remember your remind of to pay attention to thread safe.It is like the hibernate session from this aspect? | I don't know Hibernate very well but I guess it is. anonymous wrote : | But does a entitymanager hold too many resource,and i make one for each thread,the performance will be reduced? | Use entityManager.close(). Regards Felix View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4035584#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...