hibernate persist update 方法没有正常工作(不保存数据,不更新数据)

时间:2024-08-20 17:36:26

工程结构

hibernate persist update 方法没有正常工作(不保存数据,不更新数据)

问题描述

在工程中通过spring aop的方式配置事务,使用hibernate做持久化。在代码实现中使用hibernate persit()方法插入数据到数据库,使用hibernate update()方法更新数据。问题是执行这两个方法没有报错,但是也没有插入数据或者更新数据。

原因

hibernate persist()以及update()方法只有事务执行flush()或者commit()方法,才将数据写入数据库。详细内容可以阅读博客:http://www.cnblogs.com/xiaoheike/p/5374613.html。使用spring aop配置的事务,在方法运行结束之后会运行commit()方法。程序实例可以看PersonDAOImpl.java(实现方法)小结,重点原因在于spring aop事务与session自己创建的事务是两个不同的事务,虽然最后spring aop 配置的事情 commit,但是session对象的事务并没有调用commit。以下是实例程序。

事务配置(applicationContext.xml)

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd"> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/Testdb" />
<property name="username" value="root" />
<property name="password" value="123456" />
</bean> <!-- Hibernate 4 SessionFactory Bean definition -->
<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hiberante.format_sql">true</prop>
</props>
</property>
<!-- hibernate配置文件放置位置,这个配置文件似乎也没有多大的作用了 -->
<property name="configLocations">
<list>
<value>
classpath:/hibernate.cfg.xml
</value>
</list>
</property>
</bean> <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean> <tx:advice id="personServiceTxAdvice" transaction-manager="transactionManager">
<tx:attributes>
<!-- 表达式中的这些方法会执行如下的规则 -->
<tx:method name="delete*" isolation="DEFAULT" read-only="false" propagation="REQUIRED" />
<tx:method name="update*" isolation="DEFAULT" read-only="false" propagation="REQUIRED" />
<tx:method name="save*" isolation="DEFAULT" read-only="false" propagation="REQUIRED" />
<tx:method name="*" isolation="DEFAULT" read-only="false" propagation="REQUIRED" />
</tx:attributes>
</tx:advice> <aop:config>
<aop:pointcut id="personServiceTxPointcut" expression="execution(* com.journaldev.dao.PersonDAO.*(..))" />
<aop:advisor id="personServiceTxAdvisor" advice-ref="personServiceTxAdvice" pointcut-ref="personServiceTxPointcut" />
</aop:config> <bean id="personDAO" class="com.journaldev.dao.PersonDAOImpl">
<property name="sessionFactory1" ref="sessionFactory" />
<property name="sessionFactory2" ref="sessionFactory" />
</bean>
</beans>

PersonDAOImpl.java(实现方法)

package com.journaldev.dao;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction; import com.journaldev.model.Person; public class PersonDAOImpl implements PersonDAO { private SessionFactory sessionFactory1;
private SessionFactory sessionFactory2; public void setSessionFactory1(SessionFactory sessionFactory1) {
this.sessionFactory1 = sessionFactory1;
} public void setSessionFactory2(SessionFactory sessionFactory2) {
this.sessionFactory2 = sessionFactory2;
} public void save1(Person person) {
Session session1 = this.sessionFactory1.openSession();
session1.persist(person);
session1.close();
} public void save2(Person person) {
Session session1 = this.sessionFactory1.openSession();
Session session2 = sessionFactory2.openSession();
Transaction tx = session2.beginTransaction();
session1.persist(person);
tx.commit();
session2.close();
session1.close();
} public void save3(Person person) {
Session session1 = this.sessionFactory1.openSession();
Transaction tx = session1.beginTransaction();
session1.persist(person);
tx.commit();
session1.close();
} @SuppressWarnings("unchecked")
public List<Person> list() {
Session session = this.sessionFactory1.openSession();
List<Person> personList = session.createQuery("from Person").list();
session.close();
return personList;
} public Person findOne(Integer id) {
Session session = this.sessionFactory1.openSession();
Person p = (Person) session.get(Person.class, id);
session.close();
return p;
} public void delete(Person person) {
Session session = this.sessionFactory1.openSession();
session.delete(person);
session.close();
} public void update1(Person person) {
Session session = this.sessionFactory1.openSession();
session.update(person);
session.close();
} public void update2(Person person) {
Session session1 = this.sessionFactory1.openSession();
Session session2 = this.sessionFactory1.openSession();
Transaction tx = session2.beginTransaction();
session1.update(person);
tx.commit();
session2.close();
session1.close();
} public void update3(Person person) {
Session session1 = this.sessionFactory1.openSession();
Transaction tx = session1.beginTransaction();
session1.update(person);
tx.commit();
session1.close();
}
}

测试类

package com.journaldev.main;

import java.util.List;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.journaldev.dao.PersonDAO;
import com.journaldev.model.Person; public class SpringHibernateMain { public static void main(String[] args) {
test1();
test2();
test3();
} public static void test1() {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
PersonDAO personDAO = context.getBean(PersonDAO.class);
System.out.println("=================save1()==================");
// 增加一条数据
Person person = new Person();
person.setName("Pankaj");
person.setCountry("India");
personDAO.save1(person);
System.out.println("================listAll()===================");
// 检索所有数据
List<Person> list = personDAO.list();
for (Person p : list) {
System.out.println("所有记录:" + p);
}
System.out.println("================update1()===================");
// 更新一条Person记录
person.setCountry("zhongguo");
personDAO.update1(person);
System.out.println("更新一条记录India-->zhongguo:" + personDAO.findOne(person.getId()));
System.out.println("================delete()===================");
// 删除一条Person记录
personDAO.delete(person); context.close();
} public static void test2() {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
PersonDAO personDAO = context.getBean(PersonDAO.class);
System.out.println("=================save3()==================");
// 增加一条数据
Person person = new Person();
person.setName("Pankaj");
person.setCountry("India");
personDAO.save1(person);
System.out.println("================listAll()===================");
// 检索所有数据
List<Person> list = personDAO.list();
for (Person p : list) {
System.out.println("所有记录:" + p);
}
System.out.println("================update2()===================");
// 更新一条Person记录
person.setCountry("zhongguo");
personDAO.update1(person);
System.out.println("更新一条记录India-->zhongguo:" + personDAO.findOne(person.getId()));
System.out.println("================delete()===================");
// 删除一条Person记录
personDAO.delete(person); context.close();
} public static void test3() {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
PersonDAO personDAO = context.getBean(PersonDAO.class);
System.out.println("=================save3()==================");
// 增加一条数据
Person person = new Person();
person.setName("Pankaj");
person.setCountry("India");
personDAO.save3(person);
System.out.println("================listAll()===================");
// 检索所有数据
List<Person> list = personDAO.list();
for (Person p : list) {
System.out.println("所有记录:" + p);
}
System.out.println("================update3()===================");
// 更新一条Person记录
person.setCountry("zhongguo");
personDAO.update3(person);
System.out.println("更新一条记录India-->zhongguo:" + personDAO.findOne(person.getId()));
System.out.println("================delete()===================");
// 删除一条Person记录
personDAO.delete(person); context.close();
}
}

运行结果

=================save1()==================
================update1()===================
Hibernate: select person0_.id as id1_0_0_, person0_.country as country2_0_0_, person0_.name as name3_0_0_ from PERSON person0_ where person0_.id=?
更新一条记录India-->zhongguo:null =================save2()==================
================update2()===================
Hibernate: select person0_.id as id1_0_0_, person0_.country as country2_0_0_, person0_.name as name3_0_0_ from PERSON person0_ where person0_.id=?
更新一条记录India-->zhongguo:null =================save3()==================
Hibernate: insert into PERSON (country, name) values (?, ?)
================update3()===================
Hibernate: update PERSON set country=?, name=? where id=?
Hibernate: select person0_.id as id1_0_0_, person0_.country as country2_0_0_, person0_.name as name3_0_0_ from PERSON person0_ where person0_.id=?
更新一条记录India-->zhongguo:id=8, name=Pankaj, country=zhongguo

原因分析

一共有三个测试例子,第一个例子test1()方法,调用save1()方法,使用spring aop配置的事务,从输出结果可以看出,数据没有插入数据库。update1()方法与save1()方法是相同情况。

第二个例子test2()方法,调用save2()方法,persist()方法被包围在spring aop配置的事务和session2的事务中(事务有提交),从输出结果可以看出,数据没有插入数据库。update2()方法与save2()方法是相同情况。

第三个例子test3()方法,persist()方法被包围在spring aop配置的事务和session1的事务中(事务有提交),从输出结果可以看出,数据成功插入数据库。update3()方法与save3()方法是相同情况。

通过实例程序可以看出,persist(),以及update()方法需要在调用它们的session中的事务中执行,最后该session的事务需要commit。

源代码可以从github获取:https://github.com/xiaoheike/SpringHibernateWithTransactionExample,这份源代码是spring + hibernate + spring aop 配置事务的demo工程。在完成demo过程中发现该问题,一直无法理解,一周之后恍然大悟,遂写这篇博客。

教程结束,感谢阅读。

欢迎转载,但请注明本文链接,谢谢。

2016/4/15 18:38:01