spring——整合Mybatis

一、Mybatis整合spring

步骤:

导入相关jar包
- junit
- mybatis
- mysql数据库
- spring-webmvc
- aop织入
- mybatis-spring
- spring-jdbc(spring的事务管理器,也可以用druid等的代替)
编写配置文件
测试

1.1 回忆mybatis

编写实体类
编写核心配置文件
编写接口
编写Mapper.xml
测试

1.2 整合方式一

注意版本限制:

dataSource(这里配置使用Spring的数据源替换Mybatis的配置)

<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/dailyClick-test?useSSL=false&amp;useUnicode=true&amp;characterEncoding=utf-8"/>

    <property name="username" value="1111"/>

    <property name="password" value="1111"/>

</bean>

注:Mybatis有默认的数据源(连接池),但是是可以替换的

sqlSessionFactory配置

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">

    <property name="dataSource" ref="dataSource" />

    <!--        绑定配置文件地址和mapper地址-->

    <property name="configLocation" value="classpath:mybatis-config.xml"/>

    <property name="mapperLocations" value="classpath:com/guan/dao/*.xml"/>

</bean>

注意:

需要配置数据源
需要绑定配置文件地址和mapper地址,注意这里的路径使用classpath路径
由于mapper等信息被转移到<bean>中,不能重复配置(如:<mapper>),否则会报错;mybatis-config.xml配置文件通常留<typeAlias>和<settings>

与在原来的mybatis不同,整合后需要有一个接口的实现类,且接口的方法需要通过sqlSessionTemplate实现(有利于bean的注册和管理,这个sqlSessioinTemplate是线程安全的)

sqlSessionTemplate配置
```
<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">

    <constructor-arg index="0" ref="sqlSessionFactory"/>

</bean>
```
注:由于sqlSessionTemplate没有set方法,只有构造函数,所以通过<constructor>标签注入

实现类:与mybatis元素代码不同,接口类需要实现且接口的方法通过sqlSessionTemplate实现

public class UserMapperImpl implements UserMapper {

    SqlSessionTemplate sqlSession;

    public void setSqlSession(SqlSessionTemplate sqlSession) {

        this.sqlSession = sqlSession;

    }

    public List<UserBean> getUserList() {

        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        return mapper.getUserList();

    }

}

<bean id="userMapper" class="com.guan.dao.UserMapperImpl">

    <property name="sqlSession" ref="sqlSession"/>

</bean>

测试

public class MyTest {

    public static void main(String[] args) throws IOException {

        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

        UserMapperImpl userMapperImpl = context.getBean("userMapper", UserMapperImpl.class);

        List<UserBean> userList = userMapperImpl.getUserList();

        for (UserBean userBean : userList) {

            System.out.println(userBean);

        }

    }

}

注:

(1).mybatis的配置文件(指的是和spring注册的那一部分),最好通过import引入ApplicationiContext中,这样spring配置文件的结构可以区分开

(2).xxxTemplate是spring特有的模板类

1.3 整合方式二

注:SqlSessionDaoSupport:抽象类,可以通过SqlSessionFactory获得一个SqlSessionTemplate.所以该方法相对于第一种方法增加了一个抽象类,减少了一个配置SqlSessionTemplate的步骤

环境搭建:

接口:

public interface UserMapper1 {

    List<UserBean> getUserList();

}

xml实现

<?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.guan.dao.UserMapper1">

    <select id="getUserList" resultType="userBean">

        SELECT  * FROM  user;

    </select>

</mapper>

实体类:

public class UserMapper1Impl extends SqlSessionDaoSupport implements UserMapper1{

    public List<UserBean> getUserList() {

        return getSqlSession().getMapper(UserMapper1.class).getUserList();

    }

}

xml配置(在上文的前文的基础上配置)

<bean id="userMapper1" class="com.guan.dao.UserMapper1Impl">

    <property name="sqlSessionFactory" ref="sqlSessionFactory"/>

</bean>

测试:

    public static void main(String[] args) throws IOException {

        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

        UserMapper1Impl userMapperImpl = context.getBean("userMapper1", UserMapper1Impl.class);

        List<UserBean> userList = userMapperImpl.getUserList();

        for (UserBean userBean : userList) {

            System.out.println(userBean);

        }

    }

二、spring中的事物管理

编程式事务:将事务管理代码嵌到业务方法中控制事务的提交和回滚

缺点:使业务逻辑中包含额外的事务管理代码

声明式事物:使用AOP

(1).搭建环境:

接口

public interface UserMapper1 {

    List<UserBean> getUserList();

    void insert(UserBean user);

    void delete(String UId);

}

mapper:

<insert id="insert" parameterType="userBean">

    INSERT  INTO user(UId,UName,USet,UAuth,UPassword,UState) VALUES(#{UId},#{UName},#{USet},#{UAuth},#{UPassword},#{UState});

</insert>

<delete id="delete" parameterType="string">

    DELETEs FROM user WHERE UId = #{UId};

</delete>

注:可以看到我这里的"DELETEs"是错误的写法

编写实体类:

public class UserMapper1Impl extends SqlSessionDaoSupport implements UserMapper1{

    public List<UserBean> getUserList() {

        insert(new UserBean("6666666666","淀真嗣",1,0,"123456",1));

        delete("3180421016");

        return getSqlSession().getMapper(UserMapper1.class).getUserList();

    }

    public void insert(UserBean user) {

        getSqlSession().getMapper(UserMapper1.class).insert(user);

    }

    public void delete(String UId) {

        getSqlSession().getMapper(UserMapper1.class).delete(UId);

    }

}

注:getUserList中添加了insert和delete方法,且delete方法是错误的.如果没有事务,则插入可以完成;如果有事务,则插入无法完成

(2).导入事务相关的xml头文件约束,创建DataSourceTransaction对象以开启事务,配置事务通知,结合AOP实现事务的织入

<?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:tx="http://www.springframework.org/schema/tx"

       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/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">

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">

        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>

        <property name="url" value="jdbc:mysql://47.100.90.132:3306/dailyClick-test?useSSL=false&amp;useUnicode=true&amp;characterEncoding=utf-8"/>

        <property name="username" value="root"/>

        <property name="password" value="aguan123"/>

    </bean>

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">

        <property name="dataSource" ref="dataSource" />

<!--        bind mybatis-config.xml and userMapper.xml-->

        <property name="configLocation" value="classpath:mybatis-config.xml"/>

        <property name="mapperLocations" value="classpath:com/guan/dao/*.xml"/>

    </bean>

    <bean id="userMapper1" class="com.guan.dao.UserMapper1Impl">

        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>

    </bean>

<!--    配置声明式事务-->

    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">

        <property name="dataSource" ref="dataSource"/>

    </bean>

<!--    配置事务通知-->

    <tx:advice id="txAdvice" transaction-manager="transactionManager">

        <tx:attributes>

            <tx:method name="getUserList" propagation="REQUIRED"/>

        </tx:attributes>

    </tx:advice>

<!--    结合AOP织入事务-->

    <aop:config>

        <aop:pointcut id="point" expression="execution(* com.guan.dao.*.*(..))"/>

<!--        <aop:advisor advice-ref="txAdvice" pointcut-ref="point"/>-->

    </aop:config>

</beans>

注:<tx:method name="getUserList" propagation="REQUIRED"/>的propagation属性表示对这些方法怎样使用事务,如:REQUIRED表示支持当前事务，如果当前没有事务，就新建一个事务 (Default)

(3).测试

public class MyTest {

    public static void main(String[] args) throws IOException {

        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

        UserMapper1 userMapperImpl = context.getBean("userMapper1", UserMapper1.class);

        List<UserBean> userList = userMapperImpl.getUserList();

        for (UserBean userBean : userList) {

            System.out.println(userBean);

        }

    }

}

注意:由于使用了AOP,这里UserMapper1 userMapperImpl = context.getBean("userMapper1", UserMapper1.class)的返回类型必须为interface类型,而不是实体类型