整合MyBatis

1、整合MyBatis

步骤：

1. 导入相关jar包

   1. junit

   2. mybatis

   3. mysql数据库

   4. spring相关的

   5. aop织入

   6. mybatis-spring【new】

2. 编写配置文件

3. 测试

1.1、MyBatis

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>spring-study</artifactId>
        <groupId>com.kuang</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
​
    <artifactId>spring-10-mybatis</artifactId>
​
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.28</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.8</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.14</version>
        </dependency>
        <!-- Spring操作数据库的话，还需要一个spring-jdbc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.14</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.7</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.6</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.22</version>
        </dependency>
​
<!--        <dependency>-->
<!--            <groupId>cglib</groupId>-->
<!--            <artifactId>cglib</artifactId>-->
<!--            <version>3.3.0</version>-->
<!--        </dependency>-->
    </dependencies>
​
    <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>
​
​
​
​
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
​
</project>

 

1. 编写实体类

   User类

   import lombok.Data;

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

    

2. 编写核心配置文件

   mybatis-config.xml

   <?xml version="1.0" encoding="UTF8" ?>
   <!DOCTYPE configuration
           PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
           "http://mybatis.org/dtd/mybatis-3-config.dtd">
   <!-- configuration核心配置文件 -->
   <configuration>
   ​
       <typeAliases>
           <package name="com.kuang.pojo"/>
       </typeAliases>
   ​
       <environments default="development">
           <environment id="development">
               <transactionManager type="JDBC"/>
               <dataSource type="POOLED">
                   <property name="driver" value="com.mysql.jdbc.Driver"/>
                   <property name="url" value="jdbc:mysql:///mybatis?useSSL=false"/>
                   <property name="username" value="root"/>
                   <property name="password" value="root"/>
               </dataSource>
           </environment>
       </environments>
   ​
       <mappers>
           <mapper class="com.kuang.mapper.UserMapper"/>
       </mappers>
   ​
   </configuration>

    

3. 编写接口

   UserMapper

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

    

4. 编写Mapper.xml

   UserMapper.xml

   <?xml version="1.0" encoding="UTF8" ?>
   <!DOCTYPE mapper
           PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
           "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
   <!-- configuration核心配置文件 -->
   <mapper namespace="com.kuang.mapper.UserMapper">
   ​
       <select id="selectUser" resultType="com.kuang.pojo.User"><!-- resultType="User" -->
           select * from mybatis.user;
       </select>
   ​
   </mapper>

    

5. 测试

   MyTest类

   public class MyTest {
       @Test
       public void test() throws IOException {
           String resources = "mybatis-config.xml";
           InputStream in = Resources.getResourceAsStream(resources);
   ​
           SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(in);
           SqlSession sqlSession = sessionFactory.openSession(true);
   ​
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           List<User> userList = mapper.selectUser();
   ​
           for (User user : userList){
               System.out.println(user);
           }
   ​
       }
   }

    

1.2、Mybatis-spring(整合方式1)

1. 编写数据源配置

   编写spring-dao.xml

   <!-- DataSource:使用Spring的数据源替换Mybatis的配置 c3p0 dbcp druid
   我们这里使用Spring提供的JDBC org.springframework.jdbc.datasource
   -->
   ​
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///mybatis?useSSL=false"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>

    

2. sqlSessionFactory

   编写spring-dao.xmll

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

    

3. sqlSessionTemplate

   编写spring-dao.xml

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

    

4. 需要给接口加实现类【】

   UserMapperImpl类

   public class UserMapperImpl implements UserMapper{
   ​
       //我们的所有操作都使用sqlSession来执行，在原来，现在都使用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();
       }
   }

    

5. 将自己写的实现类，注入到Spring中，

   编写spring-dao.xml

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

    

6. 测试

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

    

可以将spring-dao.xmll整合进applicationContext.xml

编写applicationContext.xml配置文件

<?xml version="1.0" encoding="UTF8" ?>
<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
       https://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop
       https://www.springframework.org/schema/aop/spring-aop.xsd">
​
    <import resource="spring-dao.xml"/>
​
    <!-- -->
    <bean id="userMapper" class="com.kuang.mapper.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession" />
    </bean>
​
</beans>

 

 

1.3、Mybatis整合方式2

1. UserMapperImpl2类实现接口

   //Mybatis-plus  通用mapper
   public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{
   ​
       @Override
       public List<User> selectUser() {
           SqlSession sqlSession = getSqlSession();
           //UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           return getSqlSession().getMapper(UserMapper.class).selectUser();
       }
   }

    

2. applicationContext.xml

   <import resource="spring-dao.xml"/>
   <bean id="userMapper2" class="com.kuang.mapper.UserMapperImpl2">
       <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
   </bean>

    

3. 测试

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