Spring-12-spring整合Mybatis

12. 整合Mybatis

步骤：

1. 导入相关jar包
   • junit
   • mybatis
   • mysql数据库
   • spring相关的
   • aop织入
   • mybatis-spring【新知识点】

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.47</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.2</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.1.9.RELEASE</version>
    </dependency>
    <!--Spring操作数据库的话，还需要spring-jdbc依赖-->
    <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.1.9.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.13</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>2.0.2</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.16.10</version>
    <scope>provided</scope>
</dependency>
</dependencies> 

2. 编写配置文件

3. 测试

12.1 回忆Mybatis

1. 编写实体类

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

2. 编写核心配置类

<?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">
<!--核心配置文件-->
<configuration>
    <properties resource="db.properties"/>

    <!--可以给实体类起别名-->
    <typeAliases>
        <!--<typeAlias type="com.kuang.pojo.User" alias="User"/>-->
        <package name="com.kuang.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.kuang.mapper.UserMapper"/>
    </mappers>


</configuration>

db.properties

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

3. 编写接口

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

4. 编写mapper.xml

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

</mapper>

5. 测试

@Test
public void test1() throws IOException {
    String resource="mybatis-config.xml";
    InputStream inputStream = Resources.getResourceAsStream(resource);
    SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    SqlSession sqlSession = sqlSessionFactory.openSession();

    UserMapper mapper = sqlSession.getMapper(UserMapper.class);
    List<User> userList = mapper.selectUser();

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

解决资源过滤问题：（pom.xml）

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

12.2 Mybatis-Spring

整合方式一：SqlSessionTemplate

1. 编写数据源配置

   <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=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
       <property name="username" value="huba"/>
       <property name="password" value="123456"/>
   </bean>
   

2. sqlSessionFactory

     <!--sqlSessionFactory-->
   <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
       <property name="dataSource" ref="dataSource"/>
       <!--绑定mubatis配置文件-->
       <property name="configLocation" value="classpath:mybatis-config.xml"/>
       <property name="mapperLocations" value="classpath:com/kuang/mapper/*.xml"/>
   </bean>
   

3. sqlSessionTemplate

   <!--SqlSessionTemplate:就是我们使用的sqlSession-->
   <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
       <!--没有set方法，只能用构造器注入-->
       <constructor-arg index="0" ref="sqlSessionFactory"/>
   </bean>
   

4. 需要给接口加实现类

   public class UserMapperImpl implements UserMapper{
   
       //以前，所有的操作都使用sqlSession来执行；现在，由sqlSessionTemplate执行
       private SqlSessionTemplate sqlSession;
   
       public void setSqlSession(SqlSessionTemplate sqlSession) {
           this.sqlSession = sqlSession;
       }
   
       public List<User> selectUser() {
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           return mapper.selectUser();
   
       }
   }
   

5. 将实现类注入到spring中

   <bean id="userMapper" class="com.kuang.mapper.UserMapperImpl">
       <property name="sqlSession" ref="sqlSession"/>
   </bean>
   

6. 测试使用即可

   @Test
   public void test2(){
       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);
       }
   }
   

整合方式二： SqlSessionDaoSupport

SqlSessionDaoSupport是一个抽象的支持类，可以调用getSqlSession()得到一个SqlSessionTemplate。

实现类（继承DaoSupport）：

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{
    public List<User> selectUser() {
        /*SqlSession sqlSession = getSqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();*/
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }
}

配置bean（只需要注入sqlSessionFactory）：

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