整合mybatis-spring【spring】-优快云博客

本文详细介绍了如何在Spring框架中整合Mybatis，包括配置数据源、SqlSessionFactory、SqlSessionTemplate，以及实现Mybatis接口的多种方式。从核心配置文件、实体类、Mapper接口到测试，全面解析Mybatis-spring的使用。

12、整合Mybatis

前提：

导入相关的jar包

Junit
mybatis
mysql数据库
spring相关的
aop织入
mybatis-spring【new】

    <dependencies>
        <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>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.10.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.10.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>
    </dependencies>

    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>

12.1、回忆mybatis

编写实体类

public class User {
    private int id;   //id
    private String name;  //姓名
    private String pwd;   //密码
}

编写核心配置文件 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>
    <!--配置类的别名-->
    <typeAliases>
        <package name="com.chif.pojo"/>
    </typeAliases>

    <!-- 配置环境 -->
    <environments default="mysql">
        <!-- 配置mysql的环境 -->
        <environment id="mysql">
            <!-- 配置事务的类型 -->
            <transactionManager type="JDBC"/>
            <!-- 配置数据源(连接池) -->
            <dataSource type="POOLED">
                <!-- 配置链接数据库的4个基本信息 -->
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/test" />
                <property name="username" value="root" />
                <property name="password" value="105105" />
            </dataSource>
        </environment>
    </environments>

    <!-- 指定映射配置文件的位置，映射配置文件值指的是每个dao独立的配置文件
         如果使用注解来配置，此处应该使用class属性指定被注解的dao全限定类名
     -->

    <mappers>
        <package name="com.chif.dao"/>
     </mappers>

</configuration>

编写接口

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

编写接口对应的Mapper映射文件

<?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">
<mapper namespace="com.chif.dao.UserMapper">

    <resultMap id="usermap" type="User">
        <result property="id" column="id"/>
        <result property="name" column="username"/>
    </resultMap>

    <select id="selectUser" resultMap="usermap">
        select * from user;
    </select>

</mapper>

测试

public class MyTest {
    @Test
    public void test() throws IOException {
        String resources="mybatis-config.xml";
        InputStream in = Resources.getResourceAsStream(resources);
        //读取配置文件，获取sqlSessionFactory
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
        //创建sqlsession对象
        SqlSession sqlSession = sqlSessionFactory.openSession(true);
        //获取动态代理对象
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        //执行方法
        List<User> users = mapper.selectUser();
        for (User user : users) {
            System.out.println(user);
        }

    }
}

12.2、Mybatis-spring

编写数据源配置 DataSource

    <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/test"/>
        <property name="username" value="root"/>
        <property name="password" value="105105"/>
    </bean>

sqlSessionFactory

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

sqlSessionTemplate

  <!--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>

需要给接口加实现类【核心】

public class UserMapperImpl implements UserMapper {
    private SqlSessionTemplate sqlSession;

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

    public List<User> selectUser() {
        //获取mybatis动态代理对象，调用UserMapper.xml的Sql语句并返回结果
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();
    }
}


//提示：需要添加到IOC容器中  spring-dao.xml

将实现类注入到spring中，测试使用

在这里插入图片描述

//测试结果
User{id=41, name='老王', pwd='null'}
User{id=42, name='李四', pwd='null'}
User{id=43, name='王五', pwd='null'}
User{id=44, name='传智播客', pwd='null'}
User{id=45, name='小王', pwd='null'}
User{id=46, name='佩奇', pwd='null'}
User{id=52, name='LIU', pwd='null'}
User{id=54, name='老李', pwd='null'}
User{id=57, name='老刘', pwd='null'}

Process finished with exit code 0

12.3、简化UserMapperImpl实现类

实现类继承SqlSessionDaoSupport接口

通过getSession直接获取Session

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper  {
    public List<User> selectUser() {
        SqlSession sqlSession = getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        return userMapper.selectUser();
    }
}

在Spring中配置bean

<bean id="UserMapper2" class="com.chif.dao.UserMapperImpl2">
    <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>