Entitymanager的问题，急！！！！
大致代码如下：
EntityManagerFactory   emf   =   Persistence.createEntityManagerFactory( ".... ");

EntityManager   em   =   emf.createEntityManager();

em.getTransaction().begin();
em.persist(user);//user是一个实体bean
em.getTransaction().commit();

运行后，后台服务器提示：
15:19:55,406   ERROR   [JDBCTransaction]   JDBC   commit   failed
java.sql.SQLException:   You   cannot   commit   during   a   managed   transaction!
at   org.jboss.resource.adapter.jdbc.BaseWrapperManagedConnection.jdbcCommit(BaseWrapperManage   dConnection.java:543)
.....

------解决方案--------------------
帮你顶
------解决方案--------------------
你把事务设置成自动的试试