Spring框架(五)—Spring与Mybatis的整合

spring与mybatis整合

环境搭建

导入相关依赖

1. junit

<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
    <scope>test</scope>
</dependency>

2. mybatis

<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.5.2</version>
</dependency>

3. mysql-connector-java

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.47</version>
</dependency>

4. spring

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.3.6</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>5.3.6</version>
</dependency>

5. aspectJ AOP

<dependency>
    <groupId>org.aspectj</groupId>
    <artifactId>aspectjweaver</artifactId>
    <version>1.9.4</version>
</dependency>

6. mybatis-spring整合包

<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis-spring</artifactId>
    <version>2.0.6</version>
</dependency>

7.静态资源过滤问题

<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>
</build>

编写实体类(需要导入lombok依赖)

package com.study.pojo;
import lombok.Data;

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

编写UserMapper接口

package com.study.mapper;
import com.study.pojo.User;

import java.util.List;

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

编写UserMapper配置文件

<?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.study.mapper.UserMapper">
    <select id="selectUser" resultType="user">
        select * from mybatis.user
    </select>
</mapper>

编写mybtis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.study.pojo"/>
    </typeAliases>
</configuration>

整合方式一

要和Spring一起使用Mybatis，需要在Spring应用上下文中定义至少两样东西：一个 【SqlSessionFactory】和至少一个【数据映射类】

注意：SqlSessionFactory需要一个DataSource（数据源）。这可以任意的DataSource，只需要和其他Spring数据库连接一样配置就可以了。

一、在resource目录下创建spring-dao.xml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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--DataSource:以前在mybatis-config中配置，整合之后直接在bean中配置-->
    <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=false&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
    </bean>
    <!--sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!--name:数据源名字  ref=应用的数据源,比如dataSource引用上文中配置的数据源-->
        <property name="dataSource" ref="dataSource"/>
        <!--绑定mybatis配置文件（如果有多个mybatis配置文件）-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!--注册映射器:UserMapper.xml-->
        <property name="mapperLocations" value="classpath:com/study/mapper/*.xml"/>
        <!--这里也可以配置mybatis的所有设置，比如别名，设置是否开启日志等等,可以完全舍弃mybatis配置文件，但建议别名和日志开启在mybatis配置文件中设置-->
    </bean>
    <!--SqlSessionTemplate：就是我们使用的sqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <!--因为它没有set方法，所以只能使用构造器注入-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
</beans>

二、增加Dao接口的实现类，私有化sqlSessionTemplate

package com.study.mapper;
import com.study.pojo.User;
import org.mybatis.spring.SqlSessionTemplate;
import java.util.List;

public class UserMapperImpl implements UserMapper{
    //我们的所有操作，都使用SqlSessionTemplate；
    private SqlSessionTemplate sqlSession;

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

    @Override
    public List<User> selectUser() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();
    }
}

三、在spring配置文件中注册bean实现(不建议使用)

<bean id="userMapper" class="com.study.mapper.UserMapperImpl">
    <!--name：这个bean的sqlSession的名字，ref：引用配置好的sqlSession-->
    <property name="sqlSession" ref="sqlSession"/>
</bean>

三、新建一个spring总配置类applicationContext.xml,把实现类注入到spring中(建议使用)

<?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"/>
    <!--id：bean名字  class：要注册的实现类-->
    <bean id="userMapper" class="com.study.mapper.UserMapperImpl">
        <!--name：这个bean的sqlSession的名字，ref：引用配置好的sqlSession-->
        <property name="sqlSession" ref="sqlSession"/>
    </bean>
</beans>

四、编写测试类

import com.study.mapper.UserMapper;
import com.study.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 org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

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

public class MyTest {
    @Test
    public void test() throws IOException {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
                                                //bean的名字
        UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
        for (User user : userMapper.selectUser()) {
            System.out.println(user);
        }
    }
}

五、运行成功：

整合方式二:继承SqlSessionDataSupport

SqlSessionDataSupport是一个抽象的支持类，用来为你提供SqlSession。调用getSqlSession()方法你会得到一个SqlSessionTemplate，之后可以用于执行SQL方法。

一、编写接口实现类

package com.study.mapper;
import com.study.pojo.User;
import org.mybatis.spring.support.SqlSessionDaoSupport;
import java.util.List;

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{
    @Override
    public List<User> selectUser() {
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }
}

二、在spring中注册实现类

<bean id="userMapper2" class="com.study.mapper.UserMapperImpl2">
    <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>

三、修改上面的测试类

public class MyTest {
    @Test
    public void test() throws IOException {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
                                                //把userMapper改为userMapper2
        UserMapper userMapper = context.getBean("userMapper2", UserMapper.class);
        for (User user : userMapper.selectUser()) {
            System.out.println(user);
        }
    }
}

四、测试运行成功