初学Hibernate缓存,照着书上写的代码运行结果与书上不符合

庸世俗才 — Tue, 16 Jan 2007 10:18:00 GMT

深入浅出Hibernate P281讲到使用Hibernate3的Bulk delete/update方式删除记录时，写了段代码证明这种删除方式不能缓存同步，会从缓存中读取出数据库已经删除的信息，我依葫芦画瓢写了段代码，结果与书上结论相反，
请大家帮我看看到底怎么回事,我用的hibernate3.0,代码如下：

package mypack;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import sessionfactory.HibernateSessionFactory;

public class test2 {

/**
* @param args
*/

public static void main(String[] args) {
//储存插入记录的id
  int insertid;
  //新建实例
  TUser insertuser = new TUser();
  insertuser.setName("name1");
  insertuser.setResume("resume1");
  //插入实例
  Session session = HibernateSessionFactory.getSession();
  Transaction tx = session.beginTransaction();
  session.save(insertuser);
  insertid = insertuser.getId();
  tx.commit();
  session.close();

  // 装载插入的实例
  session = HibernateSessionFactory.getSession();
  TUser user = (TUser) session.load(TUser.class, new Integer(insertid));
  System.out.println("装载实例成功，id==>" + user.getId());
  tx = session.beginTransaction();
  // 删除插入的实例
  String hql = "delete TUser where id = "+insertid;
  Query query = session.createQuery(hql);
  query.executeUpdate();
  tx.commit();
  // 读取删除的实例，抛出异常
  user = (TUser) session.load(TUser.class, new Integer(insertid));
  System.out.println("读取缓存中存放的id成功， id==>" + user.getId());
  // 捕捉异常
  try {
   System.out.println(user.getName());
  } catch (org.hibernate.ObjectNotFoundException e) {
   System.out.println("代码user.getname()发生异常，因为该实例已经被删除");
   System.out.println(e.toString());
   System.out.println("结论：Query.execxuteUpdate()方法删除数据是缓存同步的");
  }
  session.close();
}
}

打印信息如下：

Hibernate: insert into tuser (name, resume) values (?, ?)
装载实例成功，id==>43
Hibernate: delete from tuser where id=43
读取缓存中存放的id成功， id==>43
Hibernate: select tuser0_.id as id0_, tuser0_.name as name0_0_, tuser0_.resume as resume0_0_ from tuser tuser0_ where tuser0_.id=?
代码user.getname()发生异常，因为该实例已经被删除
org.hibernate.ObjectNotFoundException: No row with the given identifier exists: [mypack.TUser#43]
结论：Query.execxuteUpdate()方法删除数据是缓存同步的

庸世俗才 2007-01-16 18:18 发表评论

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初学Hibernate缓存,照着书上写的代码运行结果与书上不符合