Spring——Spring整合Mybatis及事务

1、Mybatis-Spring整合

官网：http://mybatis.org/spring/zh/index.html

MyBatis-Spring 会帮助你将 MyBatis 代码无缝地整合到 Spring 中。

创建映射器 mapper 和 SqlSession 并注入到 bean 中。

需要的版本对应：

首先看一下包的结构

在pom.xml文件中导入相应的依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>spring02</artifactId>
        <groupId>com.jiang</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>spring04</artifactId>

    <dependencies>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.8</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!--Spring-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.10.RELEASE</version>
        </dependency>
        <!--Spring jdbc(new)-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.10.RELEASE</version>
        </dependency>
        <!--aop aspectjweaver-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>
        <!--mybatis-spring-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>

    </dependencies>

    <!-- 如果xml在java文件下，就要设置资源过滤-->
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>
</project>

编写UserMapper接口

package com.jiang.mapper;

import com.jiang.pojo.User;

import java.util.List;

public interface UserMapper {
    List<User> getUserList();
}

编写User实体类

package com.jiang.pojo;

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

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private int id;
    private String name;
    private String pwd;
}

编写UserMapper.xml文件

<?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">
<!--namespace=绑定一个对应的Dao/Mapper接口-->
<mapper namespace="com.jiang.mapper.UserMapper">

    <!--select查询语句-->
    <select id="getUserList" resultType="com.jiang.pojo.User">
       select * from mybatis.user
   </select>

</mapper>

编写applicationContext.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--整合mybatis-->

    <!--1.数据源配置-->
    <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?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>

            <!--2.注入sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
         <!--别名-->
        <property name="typeAliases" value="com.jiang.pojo.User"/>
        <!--扫描包-->
        <property name="mapperLocations" value="classpath:com/jiang/xml/*.xml"/>
    </bean>

         <!--3.创建sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>

          <!--4.放入bean-->
    <bean id="userMapperImpl" class="com.jiang.mapper.impl.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    </bean>

</beans>

在applicationContext.xml编写第3步完成后，去编写UserMapper接口的实现类UserMapperImpl，最后在去做第4步

package com.jiang.mapper.impl;

import com.jiang.pojo.User;
import com.jiang.mapper.UserMapper;
import org.mybatis.spring.SqlSessionTemplate;

import java.util.List;
//实现类
public class UserMapperImpl implements UserMapper {
    //注入sqlSession：   Spring管理了
    private SqlSessionTemplate sqlSession;


    public void setSqlSession(SqlSessionTemplate sqlSession) {
        this.sqlSession = sqlSession;
    }

    @Override
    public List<User> getUserList() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.getUserList();
    }
}

2、事务的控制

下面的所有操作基于上面操作都成功的前提下！

给UserMapper里增加添加用户和删除用户的方法

package com.jiang.mapper;

import com.jiang.pojo.User;

import java.util.List;

public interface UserMapper {
    List<User> getUserList();

    //添加用户
    int addUser(User user);


    //删除用户
    int deleteUser(int id);
}

在UserMapperImpl重写方法

package com.jiang.mapper.impl;

import com.jiang.pojo.User;
import com.jiang.mapper.UserMapper;
import org.mybatis.spring.SqlSessionTemplate;

import java.util.List;
//实现类
public class UserMapperImpl implements UserMapper {
    //注入sqlSession：   Spring管理了
    private SqlSessionTemplate sqlSession;


    public void setSqlSession(SqlSessionTemplate sqlSession) {
        this.sqlSession = sqlSession;
    }
//查询用户
    @Override
    public List<User> getUserList() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.getUserList();
    }
//添加用户
    @Override
    public int addUser(User user) {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.addUser(user);
    }
//删除用户
    @Override
    public int deleteUser(int id) {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.deleteUser(id);
    }
}

在UserMapper.xml里编写sql

<?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">
        <!--namespace=绑定一个对应的Dao/Mapper接口-->
<mapper namespace="com.jiang.mapper.UserMapper">

<!--select查询语句-->
<select id="getUserList" resultType="com.jiang.pojo.User">
       select * from mybatis.user
   </select>

<!--insert添加语句-->
<insert id="addUser" parameterType="User">
        insert into user (id,name,pwd) values (#{id},#{name},#{pwd})
    </insert>
    
    
<!--delete删除语句-->
<delete id="deleteUser" parameterType="int">
        delete from user where id=#{id}
    </delete>
</mapper>

在applicationContext.xml头文件中添加事务和AOP支持，并整合事务！

 <!--添加事务和AOP支持 我这边是在上面那些支持存在的情况下加这些 这里只是为了更简洁突出事务和AOP支持-->
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:aop="http://www.springframework.org/schema/aop"  
        http://www.springframework.org/schema/tx
        https://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/aop
        https://www.springframework.org/schema/aop/spring-aop.xsd">
                                                                  
                                                                  
                                                                  
       <!--整合事务-->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <constructor-arg ref="dataSource" />
    </bean>

    <!--事务配置增强，一定要检查pom.xml文件中有没有aop aspectjweaver 织入包-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <!--propagation 事务的传播特性 默认REQUIRED-->
            <!-- * 控制所有方法-->
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <aop:config>
        <!--切入点-->
        <aop:pointcut id="txPointCut" expression="execution(* com.jiang.mapper.*.*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut"/>
    </aop:config>

</beans>

测试

@Test
    public void test3(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapper userMapperImpl = (UserMapper) context.getBean("userMapperImpl");
        userMapperImpl.addUser(new User(4,"嘻嘻","898798"));

    }

测试成功！

注意事项：

如果把测试类中的：

UserMapper userMapperImpl = (UserMapper) context.getBean("userMapperImpl");

改为：

UserMapperImpl userMapperImpl = (UserMapperImpl) context.getBean("userMapperImpl");

会报类型转换异常：java.lang.ClassCastException: com.sun.proxy.$Proxy8 cannot be cast to com.jiang.mapper.impl.UserMapperImpl

原因解释参考博客：https://blog.csdn.net/yinzn2011/article/details/46455973

相关阅读:
连续型随机变量量函数的期望
 一个压缩级数的概率分布列
 采用积分近似级数
 关于超过几何分布
 最长游程问题
 基于递归方式解的两道题
 概率统计几道题目
 关于dede后台登陆后一片空白以及去除版权
 mac下安装xampp、及其之上的组件安装
 启用phpstorm代码提示功能
原文地址：https://www.cnblogs.com/godles/p/12368939.html