啥也不说了，直接看代码： 

 UserTransaction tran = (UserTransaction)((new InitialContext()).lookup("java:comp/UserTransaction"));
  Configuration config1 = new Configuration().configure("/hibernate1.cfg.xml");
  SessionFactory sf1=config1.buildSessionFactory();
  Configuration config2 = new Configuration().configure("/hibernate2.cfg.xml");
  SessionFactory sf2=config2.buildSessionFactory();
  
  try
  {
   tran.begin();
   Session session1=sf1.openSession();
   Session session2=sf2.openSession();
   
   CodeTable nj=new CodeTable ("aaa","bb");
   session1.save(nj);
   session1.flush();
   session1.close();
   
   session2.save(nj);
   session2.flush();
   session2.close();
   
   tran.commit();
  }
  catch(Exception e){
   tran.rollback();
   e.printStackTrace();
  }