Spring5入门-12-整合Mybatis

一、前言

环境：

  • mysql8.0.21
  • Spring 5.2.9
  • mybaits 3.5.5
  • mybatis-spring 2.0.5
  • junit 4.12

要注意的事情：

在开始使用 MyBatis-Spring 之前，你需要先熟悉 Spring 和 MyBatis 这两个框架和有关它们的术语。这很重要——因为本手册中不会提供二者的基本内容，安装和配置教程。

MyBatis-Spring 需要以下版本：

MyBatis-Spring MyBatis Spring 框架 Spring Batch Java
2.0 3.5+ 5.0+ 4.0+ Java 8+
1.3 3.4+ 3.2.2+ 2.1+ Java 6+


二、环境-回顾mybatis

2.1 依赖

        <!--mysql8-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.19</version>
        </dependency>

        <!--Spring-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>

        <!--Spring-JDBC-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>

        <!--Mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>

        <!--Mybaits-Spring-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.5</version>
        </dependency>

        <!--AOP织入-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>

        <!--JUnit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>

2.2 数据库

image-20201011154013148


2.3 pojo

package com.duzhuan.pojo;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/11 15:35
 * @Version: 1.0
 * @since: jdk11
 */
public class User {
    private int id;
    private String name;
    private String pwd;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPwd() {
        return pwd;
    }

    public void setPwd(String pwd) {
        this.pwd = pwd;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", pwd='" + pwd + '\'' +
                '}';
    }
}

2.4 mybatis配置文件

路径

image-20201011200418335

代码

mybaits-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>

    <properties resource="db.properties"/>

    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

    <typeAliases>
        <package name="com.duzhuan.pojo"/>
    </typeAliases>
    
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <mapper class="com.duzhuan.mapper.UserMapper"/>
    </mappers>
</configuration>

这里已经预先配好了mapper，请选择合适自己路径的mapper。

db.properties

driver = com.mysql.jdbc.Driver
url = jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=UTF8&serverTimezone=UTC
username = root
password = qq123456

2.5 mapper

路径

image-20201011201302297

注意事项

在此处的xml文件等配置文件，由于是Maven项目的原因，很有可能不能复制到target目录下，即真正运行的路径下没有UserMapper.xml，因此需要在pom.xml的根标签中加入以下配置：

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

代码

UserMapper:

package com.duzhuan.mapper;

import com.duzhuan.pojo.User;

import java.util.List;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/11 20:06
 * @Version: 1.0
 * @since: jdk11
 */
public interface UserMapper {
    List<User> getUserList();
}

UserMapper.xml:

<?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.duzhuan.mapper.UserMapper">
    <select id="getUserList" resultType="User">
        select * from mybatis.user
    </select>
</mapper>

2.6 测试类

路径

image-20201011204340633

代码

UserMapperTest：

package com.duzhuan.mapper;

import com.duzhuan.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.Test;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/11 20:16
 * @Version: 1.0
 * @since: jdk11
 */
public class UserMapperTest {
    @Test
    public void userMapperTest() throws IOException {
        String config = "mybatis-config.xml";

        InputStream inputStream = Resources.getResourceAsStream(config);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();

        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        List<User> userList = mapper.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }

    }
}

结果

image-20201011204427151



三、Mybatis-Spring SqlSessionTemplate

官方文档

基于以上环境，对其进行修改。

  1. 创建spring-dao.xml:

    image-20201012144705146

  2. 添加数据源:

    <?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">

    <context:property-placeholder location="db.properties"/>

    <!--使用spring的数据源替换Mybatis的配置
        这里使用spring提供的JDBC-->
    <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/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF8&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="qq123456"/>
    </bean>

</beans>

    这样就可以删掉mybatis-config.xml相关的部分：

     <properties resource="db.properties"/>

<environments default="development">
    <environment id="development">
        <transactionManager type="JDBC"/>
        <dataSource type="POOLED">
            <property name="driver" value="${driver}"/>
            <property name="url" value="${url}"/>
            <property name="username" value="${username}"/>
            <property name="password" value="${password}"/>
        </dataSource>
    </environment>
</environments>

  3. 设置mybatis配置和导入mybatis配置。其实可以完全由Spring配置，但我习惯将<settings>和typeAliases放在mybatis的配置文件中，因此会用到导入mybatis配置：

    <?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">

    <context:property-placeholder location="db.properties"/>

    <!--使用spring的数据源替换Mybatis的配置
        这里使用spring提供的JDBC-->
    <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/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF8&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="qq123456"/>
    </bean>

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

        <!--
        导入mybatis的配置
        其实可以纯spring配置mybatis，无需导入。
        -->
        <property name="configLocation" value="mybatis-config.xml"/>
        <!--比如这个，绑定UserMapper-->
        <property name="mapperLocations" value="classpath:com/duzhuan/mapper/UserMapper.xml"/>
    </bean>

</beans>

    由于有<property name="mapperLocations" value="classpath:com/duzhuan/mapper/UserMapper.xml"/>，因此可以删掉mybatis-config.xml中的：

    <mappers>
    <mapper class="com.duzhuan.mapper.UserMapper"/>
</mappers>

  4. 配置sqlSession:

    1. spring-mybatis中，是没有sqlSession的，sqlSessionTemplate等价于sqlSession。打开org.mybatis.spring.SqlSessionTemplate可以看到的是：

      image-20201012151001345

      它没有Setter方法，只能构造器注入。

    2. 在spring-dao.xml中添加：

      <!--sqlSession-->
<bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
    <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>

  5. 有了sqlSession，下一步就应该getMapper了。

    创建UserMapperImpl:

    image-20201012153207526

    代码：

    package com.duzhuan.mapper;

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

import java.util.List;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/12 15:29
 * @Version: 1.0
 * @since: jdk11
 */
public class UserMapperImpl implements UserMapper{

    private SqlSessionTemplate sqlSessionTemplate;

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

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

    在spring-dao.xml中添加：

    <!--Mapper-->
<bean id="userMapper" class="com.duzhuan.mapper.UserMapperImpl">
    <property name="sqlSessionTemplate" ref="sqlSessionTemplate"/>
</bean>

  6. 修改UserMapperTest：

    package com.duzhuan.mapper;

import com.duzhuan.pojo.User;

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

import java.io.IOException;
import java.util.List;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/11 20:16
 * @Version: 1.0
 * @since: jdk11
 */
public class UserMapperTest {
    @Test
    public void userMapperTest() throws IOException {
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
        UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
        List<User> userList = userMapper.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }
    }
}

运行测试样例结果：

image-20201012154540121

附上spring-dao.xml全代码：

<?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">

    <context:property-placeholder location="db.properties"/>

    <!--使用spring的数据源替换Mybatis的配置
        这里使用spring提供的JDBC-->
    <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/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF8&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="qq123456"/>
    </bean>

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

        <!--
        导入mybatis的配置
        其实可以纯spring配置mybatis，无需导入。
        -->
        <property name="configLocation" value="mybatis-config.xml"/>
        <!--比如这个，绑定UserMapper-->
        <property name="mapperLocations" value="classpath:com/duzhuan/mapper/UserMapper.xml"/>
    </bean>

    <!--sqlSession-->
    <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>

    <!--Mapper-->
    <bean id="userMapper" class="com.duzhuan.mapper.UserMapperImpl">
        <property name="sqlSessionTemplate" ref="sqlSessionTemplate"/>
    </bean>
</beans>


四、SqlSessionDaoSupport

官方文档-SqlSessionDaoSupport

另外一种方法。

创建一个UserMapper的实现类UserMapperDaoSupport：

image-20201012173925730

代码：

package com.duzhuan.mapper;

import com.duzhuan.pojo.User;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

/**
 * @Autord: HuangDekai
 * @Date: 2020/10/12 17:25
 * @Version: 1.0
 * @since: jdk11
 */
public class UserMapperDaoSupportImpl extends SqlSessionDaoSupport implements UserMapper {

    @Override
    public List<User> getUserList() {
        return getSqlSession().getMapper(UserMapper.class).getUserList();
    }
}

在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">

    <context:property-placeholder location="db.properties"/>

    <!--使用spring的数据源替换Mybatis的配置
        这里使用spring提供的JDBC-->
    <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/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF8&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="qq123456"/>
    </bean>

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

        <!--
        导入mybatis的配置
        其实可以纯spring配置mybatis，无需导入。
        -->
        <property name="configLocation" value="mybatis-config.xml"/>
        <!--比如这个，绑定UserMapper-->
        <property name="mapperLocations" value="classpath:com/duzhuan/mapper/UserMapper.xml"/>
    </bean>

    <!--sqlSession-->
    <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>

    <!--Mapper-->
    <bean id="userMapper" class="com.duzhuan.mapper.UserMapperImpl">
        <property name="sqlSessionTemplate" ref="sqlSessionTemplate"/>
    </bean>

<!--====================add===============-->
    <bean id="UserMapperDaoSupportImpl" class="com.duzhuan.mapper.UserMapperDaoSupportImpl">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>
<!--====================add===============-->
</beans>

运行结果：

image-20201012174241759

posted @ 2020-10-12 18:12  杜撰丶  阅读(174)  评论(0)  编辑  收藏  举报