【Spring5】Spring5基础教程(8)

前言：

本文内容：回顾MyBatis、整合Mybatis方式一、整合MyBatis方式二

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回顾Mybatis

整合前准备

导入相关jar包

junit
mybatis
mysql
spring相关
aop
mybatis-spring

<!--要引入的jar包-->
<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.22</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.6</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.3.19</version>
    </dependency>
    <!--        连接spring-jdbc-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.3.8</version>
    </dependency>
    <!--        mybatis-spring-->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>2.0.2</version>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.10</version>
    </dependency>
</dependencies>
<!--    解决资源导出问题-->
<build>
    <resources>
        <resource>
            <directory>src/main/resources</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>

编写配置文件
测试

回顾Mybatis

编写实体类

package com.jokerdig.pojo;

import lombok.Data;

/**
 * @author Joker大雄
 * @data 2022/5/23 - 13:03
 **/
@Data
public class User {
    private int id;
    private String name;
    private String pwd;
}

编写核心配置文件

<?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>
<!--    别名-->
    <typeAliases>
        <package name="com.jokerdig.pojo"/>
    </typeAliases>

    <environments default="development">

        <environment id="development">

            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=false&amp;serverTimezone=UTC"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper class="com.jokerdig.mapper.UserMapper"/>
    </mappers>
</configuration>

编写接口

package com.jokerdig.mapper;

import com.jokerdig.pojo.User;

import java.util.List;

/**
 * @author Joker大雄
 * @data 2022/5/23 - 13:25
 **/
public interface UserMapper {
    public List<User> selectUser();
}

编写Mapper.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.jokerdig.mapper.UserMapper">

    <!--    查询用户 来测试缓存-->
    <select id="selectUser" resultType="user">
        select * from user
    </select>
</mapper>

测试

package com.jokerdig.test;

import com.jokerdig.mapper.UserMapper;
import com.jokerdig.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;

/**
 * @author Joker大雄
 * @data 2022/5/23 - 13:29
 **/
public class SpringTest {

    @Test
    public void test9() throws IOException {
        String resource = "mybatis-config.xml";
        InputStream in = Resources.getResourceAsStream(resource);

        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);

        SqlSession sqlSession = factory.openSession();

        UserMapper mapper = sqlSession.getMapper(UserMapper.class);

        List<User> users = mapper.selectUser();

        for (User user : users) {
            System.out.println(user);
        }
    }
}

运行结果

User(id=1, name=admin, pwd=123)
User(id=2, name=abc, pwd=123)
User(id=3, name=def, pwd=123)
User(id=5, name=小呆瓜, pwd=33333)

Process finished with exit code 0

整合Mybatis方式一

在上方回顾代码的基础上做整合

使用SqlSessionTemplate

实现步骤

编写数据源
创建sqlSessionFactory

sqlSessionTemplate

applicationContext.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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">


<!--   1. datasource 使用spring数据源代替mybatis数据源-
            DriverManagerDataSource
-->
    <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=false&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>

<!--  2.  sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
<!--  3.      绑定mybatis-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/jokerdig/mapper/*.xml"/>
    </bean>
<!--  4.   sqlSessionTemplate 就是sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<!--        这里只能使用构造器注入 因为它没有set方法-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
<!--  5.  引入UserMapperImpl 使用 SqlSessionTemplate -->
    <bean id="userMapper" class="com.jokerdig.mapper.UserMapperImpl">
        <property name="sqlSessionTemplate" ref="sqlSession"/>
    </bean>
</beans>

需要给接口加实现类

UserMapperImpl.java

package com.jokerdig.mapper;

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

import java.util.List;

/**
 * @author Joker大雄
 * @data 2022/5/23 - 14:06
 **/
public class UserMapperImpl implements UserMapper{
    // 我们所有操作都是用SqlSessionTemplate
    private SqlSessionTemplate sqlSessionTemplate;

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

    // 查询所有
    public List<User> selectUser() {
        UserMapper mapper = sqlSessionTemplate.getMapper(UserMapper.class);
        return mapper.selectUser();
    }
}

测试

@Test
   public void test10(){
       ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
   
       UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
   
       List<User> users = userMapper.selectUser();
   
       for (User user : users) {
           System.out.println(user);
       }
   }

运行结果

User(id=1, name=admin, pwd=123)
User(id=2, name=abc, pwd=123)
User(id=3, name=def, pwd=123)
User(id=5, name=小呆瓜, pwd=33333)

Process finished with exit code 0

整合Mybatis方式二

使用SqlSessionDaoSupport

实现步骤

编写Mapper的实现类，并继承SqlSessionDaoSupport

package com.jokerdig.mapper;

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

import java.util.List;

/**
 * @author Joker大雄
 * @data 2022/5/23 - 14:23
 **/
public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{

    // 继承SqlSessionDaoSupport 可以直接getSqlSession()
    public List<User> selectUser() {
        return  getSqlSession().getMapper(UserMapper.class).selectUser();
    }
}

编写spring配置文件

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">


<!--    datasource 使用spring数据源代替mybatis数据源-
            DriverManagerDataSource
-->
    <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=false&amp;serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </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"/>
        <property name="mapperLocations" value="classpath:com/jokerdig/mapper/*.xml"/>
    </bean>
<!--    sqlSessionTemplate 就是sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<!--        这里只能使用构造器注入 因为它没有set方法-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
<!--   引入UserMapperImpl 使用 SqlSessionTemplate-->
    <bean id="userMapper" class="com.jokerdig.mapper.UserMapperImpl">
        <property name="sqlSessionTemplate" ref="sqlSession"/>
    </bean>
    <!--   引入UserMapperImpl2 使用SqlSessionDaoSupport  -->
    <bean id="userMapper2" class="com.jokerdig.mapper.UserMapperImpl2">
        <property name="sqlSessionFactory" ref="sqlSessionFactory" />
    </bean>
</beans>

测试

@Test
public void test11(){
    ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

    UserMapper userMapper = context.getBean("userMapper2", UserMapper.class);

    List<User> users = userMapper.selectUser();

    for (User user : users) {
        System.out.println(user);
    }
}

运行结果

User(id=1, name=admin, pwd=123)
User(id=2, name=abc, pwd=123)
User(id=3, name=def, pwd=123)
User(id=5, name=小呆瓜, pwd=33333)

Process finished with exit code 0