【Spring】学习笔记009--Spring整合Mybatis

　　学习完了Mybatis和Spring，一定要将它们串联起来才能够发挥最大的作用，下面我们来看看如何将Spring和Mybatis整合起来

前期准备

　　首先导入我们需要的maven依赖

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.3</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.3</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>2.0.6</version>
        </dependency>
    </dependencies>

1.方式一

　　方式一比较繁琐，需要利用到SqlSession，有点绕，需要我们多去理解一下，我们来看一下

　　mybatis配置(mybatis-config.xml、spring-dao.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>

    <typeAliases>
        <package name="com.aircl.domain"/>
    </typeAliases>
</configuration>

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

    <!--配置数据源-->
    <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/testdatabase001"/>
        <property name="username" value="root"/>
        <property name="password" value="mySQL12138"/>
    </bean>

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

        <!--绑定mybatis核心配置文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--绑定mapper.xml-->
        <property name="mapperLocations" value="classpath:com/aircl/dao/*.xml"/>
    </bean>

    <!--配置sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
</beans>

　　Spring配置(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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <import resource="spring-dao.xml"/>

    <bean id="user" class="com.aircl.domain.User"/>
    <bean id="userDao" class="com.aircl.dao.UserDaoImpl">
        <property name="sqlSession" ref="sqlSession"/>
    </bean>
    <bean id="userService" class="com.aircl.service.UserServiceImpl">
        <property name="userDao" ref="userDao"/>
    </bean>

</beans>

　　domain层

@Alias("user")
public class User implements Serializable {
    private int id;
    private String userName;
    private Date birthday;
    private String sex;
    private String address;

    public int getId() {
        return id;
    }

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

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", userName='" + userName + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

　　dao层

　　在这种方式中需要使用到DaoImpl来通过注入SqlSession拿到Mapper.xml

public interface UserDao {
    public List<User> selectUser();
}

public class UserDaoImpl implements UserDao {
    private SqlSessionTemplate sqlSession;

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

    public List<User> selectUser() {
        UserDao userDao = sqlSession.getMapper(UserDao.class);
        return userDao.selectUser();
    }
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.aircl.dao.UserDao">
    <select id="selectUser" resultType="com.aircl.domain.User">
        select * from user
    </select>
</mapper>

　　service层

public interface UserService {
    public List<User> selectUser();
}

public class UserServiceImpl implements UserService {
    private UserDaoImpl userDao;

    public void setUserDao(UserDaoImpl userDao) {
        this.userDao = userDao;
    }

    public List<User> selectUser() {
        return userDao.selectUser();
    }
}

　　测试

　　测试时我们直接拿到applicationContext.xml就可以跑起来

public class MyTest {
    @Test
    public void testUser(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserService userService = (UserService) context.getBean("userService");
        for (User user : userService.selectUser()) {
            System.out.println(user.toString());
        }
    }
}

 

 

2.方式二

　　第二种方式很简单，是我常用的方式，我们不需要使用SqlSession去拿Mapper.xml，我们使用MapperScanner去扫描我们的dao包，自动将mapper注册到spring中，简单快捷，下边我们来看一看

　　mybatis配置

<?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.aircl.domain"/>
    </typeAliases>
</configuration>

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

    <!--配置数据源-->
    <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/testdatabase001"/>
        <property name="username" value="root"/>
        <property name="password" value="mySQL12138"/>
    </bean>

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

        <!--绑定mybatis核心配置文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--绑定mapper.xml-->
        <property name="mapperLocations" value="classpath:com/aircl/dao/*.xml"/>
    </bean>

    <bean id="mapperScanner" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.aircl.dao"/>
    </bean>
</beans>

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

    <import resource="spring-dao.xml"/>

    <bean id="user" class="com.aircl.domain.User"/>
    <bean id="userService" class="com.aircl.service.UserServiceImpl">
        <property name="userDao" ref="userDao"/>
    </bean>

</beans>

　　domain层

package com.aircl.domain;

import org.apache.ibatis.type.Alias;

import java.io.Serializable;
import java.util.Date;

/**
 * Description :
 *
 * @author : AirCL
 * Date : 2021/2/6
 * Time : 14:11
 */
@Alias("user")
public class User implements Serializable {
    private int id;
    private String userName;
    private Date birthday;
    private String sex;
    private String address;

    public int getId() {
        return id;
    }

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

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", userName='" + userName + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

　　dao层

　　这种方式的dao层不需要DaoImpl去拿SqlSession取Mapper.xml，直接一个dao接口+Mapper.xml即可

public interface UserDao {
    public List<User> selectUser();
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.aircl.dao.UserDao">
    <select id="selectUser" resultType="com.aircl.domain.User">
        select * from user
    </select>
</mapper>

　　service层

　　service层也不需要使用DaoImpl对象，直接使用Dao接口对象即可，mapperscanner会将dao接口注册到spring中，以供我们使用

public interface UserService {
    public List<User> selectUser();
}

public class UserServiceImpl implements UserService {
    private UserDao userDao;

    public void setUserDao(UserDao userDao) {
        this.userDao = userDao;
    }

    public List<User> selectUser() {
        return userDao.selectUser();
    }
}

　　测试

public class MyTest {
    @Test
    public void testUser(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserService userService = (UserService) context.getBean("userService");
        for (User user : userService.selectUser()) {
            System.out.println(user.toString());
        }
    }
}