hibernate 更新对象updateobject

 加载对象，调用session的update（）方法，让对象处于持久化状态的时候进行更新操作，代码如下所示。

  //测试方法以test开头.测试update方法.返回存在的加载的.

           publicvoid testUpdate2()

           {

               Sessionsession =null;

               

               try

               {

                  session= HibernateUtils.getSession();

                  //开启事务.

                  session.beginTransaction();

                  //采用load查询不存在的数据,hibernate会抛出object not found exception

                  

                  //先把要更新的查出来.

                  //建议采用此种方式,先加载再更新的方式.

                  Useruser = (User)session.load(User.class,"402881e5441bfb0601441bfb075b0002");

                  //查出来的话就直接放入了.处于持久化状态.

                  user.setName("周日");

                  

                  //显示的调用,因为为持久化状态也可以不显示调用.

                  session.update(user);

                  

                  

                  //提交事务.把内存的改变提交到数据库上.

                  session.getTransaction().commit();

                  

               }catch(Exceptione){

                  e.printStackTrace();

                  session.getTransaction().rollback();

               }finally{

                  HibernateUtils.closeSession(session);

               }

               

           }