Spring之mybatis整合一

spring整合mybatis步骤如下：

1、导入依赖包，尤其是，mybatis-spring的依赖

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>
        <!-- mybatis依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>
    </dependencies>
    <!--    在bulid中配置resource,防止出现ExceptionInInitializerError问题，
资源导出失败，即mapper.xml无法导出-->
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                    <include>**/*.properties</include>
                </includes>
            </resource>

            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.xml</include>
                    <include>**/*.properties</include>
                </includes>
            </resource>
        </resources>
    </build>
</project>

2、spring-dao.xml：配置数据库、sqlSessionFactory、sqlSessionTemplate、以及注册UserMapperImpl实现类

<?xml version="1.0" encoding="UTF-8"?>
<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
        https://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--配置bean-->
    <!--配置数据库-->
    <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&amp;useUnicode=true&amp;characterEncoding=UTF-8&amp;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mybatis-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--绑定mapper.xml-->
        <property name="mapperLocations" value="classpath:com/lizheng/dao/UserMapper.xml"/>
    </bean>
    <!--sqlSessionTemplate-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory" />
    </bean>
    <!--注册接口实现类-->
    <bean id="userMapper" class="com.lizheng.dao.UserMapperImpl">
        <property name="sqlSessionTemplate" ref="sqlSession"/>
    </bean>
    
</beans>

 而在mybatis-config.xml中只需要配置settings以及typeAliases

<?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>
    <!--给实体类起别名-->
<!--    <settings>-->
<!--        <setting name="" value=""/>-->
<!--    </settings>-->
    <typeAliases>
        <typeAlias type="com.lizheng.pojo.User" alias="User"/>
    </typeAliases>

</configuration>

3、编写UserMapperImpl实现类，使用sqlSessionTemplate来操作

public class UserMapperImpl implements UserMapper {
    private SqlSessionTemplate sqlSessionTemplate;

    public void setSqlSessionTemplate(SqlSessionTemplate sqlSessionTemplate) {
        this.sqlSessionTemplate = sqlSessionTemplate;
    }

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

    @Override
    public int update(User user) {
        return sqlSessionTemplate.getMapper(UserMapper.class).update(user);
    }

    @Override
    public int delete(int id) {
        return sqlSessionTemplate.getMapper(UserMapper.class).delete(id);
    }

    @Override
    public int addUser(User user) {
        return sqlSessionTemplate.getMapper(UserMapper.class).addUser(user);
    }
}

4、测试类

public class MyTest {

    @Test
    public void myTset(){
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
        UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
        List<User> userList = userMapper.getUser();
        for (User user : userList) {
            System.out.println(user);
        }
    }
}