Spring入门学习(七)

Spring整合MyBatis

官网：http://mybatis.org/spring/zh/index.html

方式一：

1、导入相关的jar包

• junt
• mybatis
• 连接数据库
• 操作数据库
• spring相关的
• aop织入包
• lombok
• mybatis-spring整合包

注意版本：

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</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>5.1.9.RELEASE</version>
        </dependency>
        <!--spring操作数据库的包-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.9.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>2.0.3</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
        </dependency>
    </dependencies>

    <!--配置资源资源过滤-->
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>

2、编写实体类、接口、接口配置文件

1、实体类

package com.star.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private int id;
    private String name;
    private String pwd;
}

2、接口

package com.star.mapper;

import com.star.pojo.User;

import java.util.List;

public interface UserMapper {

    public List<User> getUserList();

    public int addUser(User user);

    public int deleteUser(int id);

}

3、接口配置文件

<?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.star.mapper.UserMapper">

    <select id="getUserList" resultType="user">
        select * from user;
    </select>

    <insert id="addUser" parameterType="user">
        insert into user (id,name,pwd) values (#{id},#{name},#{pwd});
    </insert>

    <delete id="deleteUser" parameterType="int">
        delete from user where id=#{id};
    </delete>

</mapper>

3、编写mybatis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.star.pojo"/>
    </typeAliases>
</configuration>

4、编写spring配置文件

1、配置文件的约束文件

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

2、数据整合

    <!--选择jdbc包下的DriverManagerDataSource-->
    <bean id="dateSources" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf8"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>

3、注入sqlSessionFactory

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!--导入数据源-->
        <property name="dataSource" ref="dateSources"/>
        <!--绑定mybatis-config.xml文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--扫描接口对应的配置文件-->
        <property name="mapperLocations" value="classpath:com/star/mapper/*.xml"/>
    </bean>

4、注入sqlsession

    <!--使用构造器注入-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <!--index="0"：给第一个参数赋值 将sqlSessionFactory赋值给参数 可以点进源码查看-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>

5、编写接口的实现类来使用sqlSeeion

package com.star.mapper.impl;

import com.star.mapper.UserMapper;
import com.star.pojo.User;
import org.mybatis.spring.SqlSessionTemplate;

import java.util.List;

public class UserMapperImpl implements UserMapper {

    //我们所有的操作,原来都使用sqlSession来执行，现在使用SqlSessionTemplate，作为 SqlSession 的一个实现，SqlSessionTemplate 是线程安全的，可以被多个 DAO 或映射器所共享使用。
    private SqlSessionTemplate sqlSession;

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

    public List<User> getUserList() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        return mapper.getUserList();
    }

    public int addUser(User user) {
        return 0;
    }

    public int deleteUser(int id) {
        return 0;
    }
}

6、将实现类中的sqlSession装配

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

5、编写测试类进行测试

import com.star.mapper.UserMapper;
import com.star.pojo.User;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.List;

public class MyTest {
    
    @Test
    public void getUserListTest2(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapper userMapperImpl = (UserMapper) context.getBean("userMapperImpl");
        List<User> userList = userMapperImpl.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }
    }
}

测试结果：

如果我们要进行增删改查，只需要改变sqlSession操作类中的mapperMethods方法中的代码，然后编写测试类就可以了！

方式二：

1、编写sqlSession类

package com.star.mapper.impl;

import com.star.mapper.UserMapper;
import com.star.pojo.User;
import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

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

    public int addUser(User user) {
        return 0;
    }

    public int deleteUser(int id) {
        return 0;
    }
}

2、修改之前的spring配置文件

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

    <!--数据整合-->
    <!--选择jdbc包下的DriverManagerDataSource-->
    <bean id="dateSources" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf8"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>

    <!--注入sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dateSources"/>
        <!--绑定mybatis-config.xml文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--<property name="typeAliasesPackage" value="com.star.pojo"/>-->
        <property name="mapperLocations" value="classpath:com/star/mapper/*.xml"/>
    </bean>

    <bean id="userMapperImpl2" class="com.star.mapper.impl.UserMapperImpl2">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>

</beans>

3、编写测试类

    @Test
    public void getUserListTest(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapper userMapperImpl2 = (UserMapper) context.getBean("userMapperImpl2");
        List<User> userList = userMapperImpl2.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }
    }

测试结果：

相比之下，方式二比较简便，但是在刚开始学的时候，先使用方式一，熟练后再使用方式二！

还有：增删改操作需要开启事务，所以需要再Spring配置文件中配置事务，我们下篇再说！