Spring & Mybatis 整合

Spring & Mybatis 整合

目录结构：

所需要得Jar包：

<dependencies>
        <!-- spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>
        <!--junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13-beta-1</version>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.0</version>
        </dependency>
        <!--mysql驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!--spring-jdbc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.4.RELEASE</version>
        </dependency>
        <!--aspectjweaver-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.5</version>
        </dependency>
        <!--mybatis-spring-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.3</version>
        </dependency>
        <!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
            <scope>provided</scope>
        </dependency>
        <!--druid-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.21</version>
        </dependency>
    </dependencies>

1、编写实体类、接口、映射文件、db.properties、mybatis-config.xml、spring-dao.xml

实体类：

package com.xu.pojo;

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

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

接口：

package com.xu.mapper;

import com.xu.pojo.Users;

import java.util.List;

public interface UsersMapper {
    public List<Users> select();
}

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.xu.mapper.UsersMapper">
    <select id="select" resultType="users">
        select * from mybatis.user
    </select>
</mapper>

db.properties:

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=UTF-8
username=root
password=123456

---

mybatis-config.xml:

虽然可以全部在spring配置，还是把别名和注册Mapper放到这里

<?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.xu.pojo"/>
    </typeAliases>
   
    <!--每一个xxxMapper.xml都要在这里注册-->
    <mappers>
        <mapper resource="com/xu/mapper/UsersMapper.xml"/>
    </mappers>
</configuration>

spring-dao.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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
	<!--加载db.properties-->
    <context:property-placeholder location="db.properties" system-properties-mode="NEVER"/>
    
    <!--配置数据源-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <property name="driverClassName" value="${driver}"/>
        <property name="url" value="${url}"/>
        <property name="username" value="${username}"/>
        <property name="password" value="${password}"/>
    </bean>
    <!--sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
    </bean>

    <bean id="usermapper" class="com.xu.mapper.UserMapperImpl">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>
</beans>

2、编写实现类(UserMapperImpl)，并注册到Spring

package com.xu.mapper;

import com.xu.pojo.Users;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

public class UserMapperImpl extends SqlSessionDaoSupport implements UsersMapper {
    @Override
    public List<Users> select() {
        return getSqlSession().getMapper(UsersMapper.class).select();
    }
}

3、测试

import com.xu.mapper.UsersMapper;
import com.xu.pojo.Users;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;

public class MyTest {
    @Test
    public void Test01() throws IOException {
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
        UsersMapper usermapper = context.getBean("usermapper", UsersMapper.class);
        for (Users users : usermapper.select()) {
            System.out.println(users);
        }
    }
}