2021-07-13发表2021-07-14更新学习4 分钟读完 (大约531个字)

Spring整合Mybatis

步骤：

导入相关jar包

junit
mybatis
mysql数据库
spring相关
aop织入
mybatis-spring

<dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>5.7.2</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.7</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.25</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.7</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.6</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
        </dependency>

编写配置文件
测试

回忆MyBatis

编写实体类

package com.lrr.pojo;

import lombok.Data;

/**
 * TODO
 *
 * @author DD
 * @version 1.0
 * @date 2021/7/13 17:20
 */
@Data
public class User {
    private int id;
    private String name;
    private String perms;
}

编写核心配置文件

<?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>




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

    <environments default="development">
        <!-- 数据库环境 -->
        <environment id="development">
            <!-- 使用JDBC使用管理 -->
            <transactionManager type="JDBC"/>
            <!-- 数据源配置 -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
                <property name="username" value="root"/>
                <property name="password" value="lrr1996429"/>
            </dataSource>
        </environment>
    </environments>

    <!-- 映射器 -->
    <mappers>
<!--        <mapper resource="UserMapper.xml"/>-->
        <mapper class="com.lrr.mapper.UserMapper" />
    </mappers>
</configuration>

编写接口

package com.lrr.mapper;

import com.lrr.pojo.User;

import java.util.List;

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

编写Mapper.xml

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


</mapper>

测试

import com.lrr.mapper.UserMapper;
import com.lrr.pojo.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.jupiter.api.Test;

import javax.annotation.Resource;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

/**
 * TODO
 *
 * @author DD
 * @version 1.0
 * @date 2021/7/13 17:34
 */
public class MyTest {
    @Test
    public void test1() throws IOException {
        String resources = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resources);
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sessionFactory.openSession(true);

        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        List<User> users = mapper.selectUser();

        System.out.println(users);
        sqlSession.close();


    }
}

Mybatis-spring

编写数据源配置

<!--DataSoure：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.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
        <property name="username" value="root"/>
        <property name="password" value="lrr1996429"/>
    </bean>

对应mybatis-config.xml中的数据源配置

sqlSessionFactory

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />

<!--        绑定Mybatis配置文件，这两个必须要，具体内容见spring-10 -->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/lrr/mapper/*.xml"/>
    </bean>

对应

1	SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);

sqlSessionTemplate

<!--    这个就是之前使用的sqlSession-->
    <bean id="sqlSessiomTemplate" class="org.mybatis.spring.SqlSessionTemplate">
<!--        因为它没有set方法只能用构造器注入-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>

对应

1	SqlSession sqlSession = sessionFactory.openSession(true);

需要给接口加实现类

package com.lrr.mapper;

import com.lrr.pojo.User;
import org.mybatis.spring.SqlSessionTemplate;

import java.util.List;

/**
 * TODO
 *
 * @author DD
 * @version 1.0
 * @date 2021/7/13 20:06
 */
public class UserMapperImpl implements UserMapper{
    // 我们的所有操作，原来都使用sqlSession来执行

    private SqlSessionTemplate sqlSession;

    public void setSqlSession(SqlSessionTemplate sqlSession)
    {
        this.sqlSession = sqlSession;
    }
    public List<User> selectUser() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();
    }
}

将自己写的实现类，注入到Spring中

1
2
3

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

测试使用

@Test
public void test2(){
    ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
    UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
    System.out.println(userMapper.selectUser());
}