Spring声明式事务

先把所有代码都放上来：

1，实体类：User.java

package com.maolei.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

//使用lombok
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private int id;
    private String name;
    private String pwd;

}

2：接口：UserMapper.java

package com.maolei.mapper;

import java.util.List;

import com.maolei.pojo.User;

public interface UserMapper {
    public List<User> selectUser();
    public int addUser(User user);
    public int deleteUser(int id);

}

3：接口实现类：UserMapperImpl.java

package com.maolei.mapper;

import java.util.List;

import org.mybatis.spring.support.SqlSessionDaoSupport;

import com.maolei.pojo.User;

public class UserMapperImpl extends SqlSessionDaoSupport implements UserMapper{

    public int addUser(User user) {
        return getSqlSession().getMapper(UserMapper.class).addUser(user);
    }

    public int deleteUser(int id) {
        return getSqlSession().getMapper(UserMapper.class).deleteUser(id);
    }

    public List<User> selectUser() {
        User user = new User(5,"王力宏","857857");
        addUser(user);
        deleteUser(1);
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }

}

4：接口的映射文件：UserMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.maolei.mapper.UserMapper">
    <select id="selectUser" resultType="user">
        select * from user;
    </select>
    <insert id="addUser" parameterType="user">
        insert into user(id,name,pwd) value(#{id},#{name},#{pwd})
    </insert>
    <delete id="deleteUser" parameterType="int">
        deletes from user where id =#{id}
    </delete>
</mapper>

注意这里故意把delete写成deletes，让sql执行出错

5：mybatis-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <typeAliases>
        <!-- <typeAlias alias="User" type="com.maolei.pojo.User"/> -->
        <package name="com.maolei.pojo"/>
    </typeAliases>
</configuration>

6：spring-dao.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
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/tx
        https://www.springframework.org/schema/tx/spring-tx.xsd">
    
    <!-- dataSource:使用Spring的数据源替换Mybatis的配置 c3p0 dbcp druid 
    我们这里使用的Spring提供的JDBC：org.springframework.jdbc.datesource -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useUnicode=true&amp;characterEncoding=UTF-8&amp;useSSL=false&amp;serverTimezone=GMT"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>
    <!-- sqlsessionFactory -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
          <property name="dataSource" ref="dataSource" />
          <!-- 绑定Mybatis配置文件 -->
          <property name="configLocation" value="classpath:mybatis-config.xml"/>
          <property name="mapperLocations" value="classpath:com/maolei/mapper/*.xml"/>
    </bean>
    <!-- sqlsessionTemplate:就是我们使用的sqlsession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
    
    <!-- 配置声明式事务 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
          <constructor-arg ref="dataSource" />
    </bean>
    <!-- 结合AOP实现事务的织入 -->
    <!-- 配置事务通知 -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <!-- 给哪些方法配置事务 -->
        <!-- 配置事务的传播特性：new propagation -->
        <tx:attributes>
            <tx:method name="addUser" propagation="REQUIRED"/>
            <tx:method name="delete*" propagation="REQUIRED"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>
    <!-- 配置事务切入 -->
    <aop:config>
        <aop:pointcut expression="execution(* com.maolei.mapper.*.*(..))" id="txPointCut"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut"/>
    </aop:config>


</beans>

这个xml里加粗的部分们就是spring声明式事务的体现。

这里注意下Spring中propagation的7种事务配置

• Spring中七种Propagation类的事务属性详解：

REQUIRED：支持当前事务，如果当前没有事务，就新建一个事务。这是最常见的选择。

SUPPORTS：支持当前事务，如果当前没有事务，就以非事务方式执行。

MANDATORY：支持当前事务，如果当前没有事务，就抛出异常。

REQUIRES_NEW：新建事务，如果当前存在事务，把当前事务挂起。

NOT_SUPPORTED：以非事务方式执行操作，如果当前存在事务，就把当前事务挂起。

NEVER：以非事务方式执行，如果当前存在事务，则抛出异常。

NESTED：支持当前事务，如果当前事务存在，则执行一个嵌套事务，如果当前没有事务，就新建一个事务。

另外，<tx:method name="..."/>里的name定义是根据正则表达式匹配接口中的方法名，上面的xml中的三种name定义，分别能匹配到addUser，deleteUser，所有方法。

7.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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">
    
    <import resource="spring-dao.xml"/>
    
    <bean id="userMapper" class="com.maolei.mapper.UserMapperImpl">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>


</beans>

8：测试类：MyTest.java

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test;
import org.mybatis.spring.SqlSessionTemplate;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.maolei.mapper.UserMapper;
import com.maolei.pojo.User;

public class MyTest {
    @Test
    public void getUser() throws IOException {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapper userMapper = context.getBean("userMapper",UserMapper.class);
        List<User> userList = userMapper.getUser();
        for (User user : userList) {
            System.out.println(user);
        }
    }

}

测试结果：

### Error updating database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'deletes from user where id =1' at line 1

先执行的addUser方法插入的数据也没有提交在数据库中