Spring整合Mybatis

步骤：

1. 导入相关依赖
   • junit
   • mybatis
   • mysql数据库
   • spring相关
   • sop织入
   • mybatis-spring【new】

<dependency>
            <groupId>junitgroupId>
            <artifactId>junitartifactId>
            <version>4.12version>
            <scope>testscope>
        dependency>
        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
            <version>8.0.30version>
        dependency>
        
        <dependency>
            <groupId>org.mybatisgroupId>
            <artifactId>mybatisartifactId>
            <version>3.5.2version>
        dependency>
        
        <dependency>
            <groupId>org.springframeworkgroupId>
            <artifactId>spring-webmvcartifactId>
            <version>5.2.0.RELEASEversion>
        dependency>
        
        <dependency>
            <groupId>org.springframeworkgroupId>
            <artifactId>spring-jdbcartifactId>
            <version>5.2.0.RELEASEversion>
        dependency>
        <dependency>
            <groupId>org.aspectjgroupId>
            <artifactId>aspectjweaverartifactId>
            <version>1.9.4version>
        dependency>
        <dependency>
            <groupId>org.mybatisgroupId>
            <artifactId>mybatis-springartifactId>
            <version>2.0.2version>
        dependency>

2. 编写类
   2.1、编写一个接口

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

2.2、编写一个接口的实现类，用于实现接口中的方法。

public class UserMapperImpl implements UserMapper{

    //我们所有的操作,都使用sqlSession来执行,现在都使用SqlSessionTemplate;
    private SqlSessionTemplate sqlSession;

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

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

3. 编写配置文件
   3.1、编写一个spring配置文件spring-dao.xml用于生成bean对象sqlSession、数据源以及其他bean对象等与数据库有关的bean。

<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
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=UTF-8"/>
        <property name="username" value="root"/>
        <property name="password" value="Yan1029."/>
    bean>

    
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/study/mapper/*.xml"/>
    bean>

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

    <bean id="userMapper" class="com.study.mapper.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    bean>
beans>

2.2、编写一个总的applicationContext.xml，导入spring-dao.xml

<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
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <import resource="spring-dao.xml"/>

    <bean id="userMapper" class="com.study.mapper.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    bean>
beans>

2.3、编写UserMapper.xml

DOCTYPE mapper
        PUBLIC "-//mybatis.org//OTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.study.mapper.UserMapper">

    <select id="selectUser" resultType="user">
    select * from mybatis.user;
    select>

mapper>

2.4、编写mybatis-config.xml

DOCTYPE configuration
        PUBLIC "-//mybatis.org//OTD Config 3.0//EN"
        "http://mybatis.org/schema/mybatis-3-config.dtd">

<configuration>


        




    <typeAliases>
        <package name="com.study.pojo"/>
    typeAliases>

configuration>

3. 测试

@Test
    public void test(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

        UserMapper mapper = context.getBean("userMapper", UserMapper.class);

        List<User> users = mapper.selectUser();

        for (User user : users) {
            System.out.println(user);
        }
    }

第二种方式

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{
    @Override
    public List<User> selectUser() {
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }

}

spring-dao.xml

<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
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=UTF-8"/>
        <property name="username" value="root"/>
        <property name="password" value="Yan1029."/>
    bean>

    
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/study/mapper/*.xml"/>
    bean>

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

applicationContext.xml中注册

    
<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
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <import resource="spring-dao.xml"/>

    <bean id="userMapper2" class="com.study.mapper.UserMapperImpl2">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
     bean>
beans>