在Spring+MyBatis组合中使用事务

　　 通过Spring和MyBatis的组合，给出一个较为详细的实例

　　代码清单：配置Spring+MyBatis测试环境

<?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:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.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
      http://www.springframework.org/schema/context  http://www.springframework.org/schema/context/spring-context-4.0.xsd">

    <!--启用扫描机制，并指定扫描对应的包-->
    <context:annotation-config/>
    <context:component-scan base-package="com.ssm.chapter13.*"/>

    <!-- 数据库连接池 -->
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/springmvc?useSSL=false&amp;serverTimezone=Hongkong&amp;characterEncoding=utf-8&amp;autoReconnect=true"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
        <property name="maxActive" value="255"/>
        <property name="maxIdle" value="5"/>
        <property name="maxWait" value="10000"/>
    </bean>

    <!-- 集成MyBatis -->
    <bean id="SqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!--指定MyBatis配置文件-->
        <property name="configLocation" value="classpath:ssm/chapter13/mybatis-config.xml"/>
    </bean>

    <!-- 事务管理器配置数据源事务 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!-- 使用注解定义事务 -->
    <tx:annotation-driven transaction-manager="transactionManager"/>

    <!-- 采用自动扫描方式创建mapper bean -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.ssm.chapter13"/>
        <property name="SqlSessionFactory" ref="SqlSessionFactory"/>
        <property name="annotationClass" value="org.springframework.stereotype.Repository"/>
    </bean>

</beans>

　　代码清单：POJO类——Role.java

package com.ssm.chapter13.pojo;

public class Role {
    private Long id;
    private String roleName;
    private String note;
}

　　代码清单：搭建MyBatis的RoleMapper.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.ssm.chapter13.mapper.RoleMapper">

    <insert id="insertRole" parameterType="com.ssm.chapter13.pojo.Role">
        insert into t_role (role_name, note)
        values (#{roleName}, #{note})
    </insert>

</mapper>

　　代码清单：RoleMapper接口

package com.ssm.chapter13.mapper;

import com.ssm.chapter13.pojo.Role;
import org.springframework.stereotype.Repository;

@Repository
public interface RoleMapper {
    public int insertRole(Role role);

}

　　代码清单：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>
    <!-- 指定映射器路径 -->
    <mappers>
        <mapper resource="ssm/chapter13/mapper/RoleMapper.xml"/>
    </mappers>
</configuration>

　　代码清单：操作角色的两个接口

public interface RoleService {

    public int insertRole(Role role);

}

public interface RoleListService {

    public int insertRoleList(List<Role> roleList);

}

　　代码清单：两个接口的实现类

@Service
public class RoleServiceImpl implements RoleService {

    @Autowired
    private RoleMapper roleMapper;

    @Override
    @Transactional(propagation = Propagation.REQUIRES_NEW, isolation = Isolation.READ_COMMITTED)
    public int insertRole(Role role) {
        return roleMapper.insertRole(role);
    }

}

@Service
public class RoleListServiceImpl implements RoleListService {

    Logger log = Logger.getLogger(RoleListServiceImpl.class);

    @Autowired
    private RoleService roleService;

    @Override
    @Transactional(propagation = Propagation.REQUIRED, isolation = Isolation.READ_COMMITTED)
    public int insertRoleList(List<Role> roleList) {
        int count = 0;
        for (Role role : roleList) {
            try {
                count += roleService.insertRole(role);
            } catch (Exception ex) {
                log.info(ex);
            }
        }
        return count;
    }
}

　　代码清单：测试隔离级别和传播行为——Chapter13Main.java

public class Chapter13Main {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext("ssm/chapter13/spring-cfg.xml");
        RoleListService roleListService = ctx.getBean(RoleListService.class);
        List<Role> roleList = new ArrayList<Role>();
        for (int i = 1; i <= 2; i++) {
            Role role = new Role();
            role.setRoleName("role_name_" + i);
            role.setNote("note_" + i);
            roleList.add(role);
        }
        int count = roleListService.insertRoleList(roleList);
        System.out.println(count);
    }

}

　　由于保存点技术并不是每一个数据库都能支持的，所以当你把传播行为设置为NESTED时，Spring会先去探测当前数据库是否能够支持保存点技术。如果数据库不予支持，它就会和REQUIRES_NEW一样创建新事务去运行代码，以达到内部方法发生异常时并不回滚当前事务的目的。

文章来源:ssm13.6