spring整合mybatis(详细)

整合Mybatis

项目整体结构：

1.导入相关jar包

        <!--导入mybatis的依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>

        <!--导入mysql的依赖-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.21</version>
        </dependency>

        <!--导入spring的依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.9</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.9</version>
        </dependency>		
		<!-- mybatis-spring整合包 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>

		<!--aop织入包-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.7</version>
        </dependency>

		<!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>

        <!--引入测试包-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>

2.编写一个基本的实体类

@Data
public class User {
    private int id;
    private String username;
    private String address;
}

3.编写一个简单的查询接口

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

4.编写mapper文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mapper.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.lili.dao.UserMapper">
    <select id="select" resultType="com.lili.entity.User">
        select *
        from user;
    </select>
</mapper>

5.编写几个配置文件

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>

    <settings>
        <!--标准日志工厂实现-->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

</configuration>

applicatinContext.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">

    <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?serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>

    <!--sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!--绑定Mabatis配置文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>
    </bean>

    <!--SqlSessionTemplate:就是我们使用的sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <!--只能使用构造器注入sqlSessionFactory，因为它没有set方法-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>


</beans>

6.增加一个Dao接口的实现类

public class UserMapperImpl implements UserMapper {
    private SqlSessionTemplate sqlSession;

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

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

7.在applicationContext.xml里面注册bean实现

    <bean id="userMapper"class="com.lili.dao.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    </bean>

8.编写测试：

    public void test1() {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapperImpl userMapper = context.getBean("userMapper", UserMapperImpl.class);
        userMapper.select().forEach(System.out::println);
    }

结果成功输出！