Spring学习笔记-整合MyBatis

Spring学习笔记-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

   <dependencies>
       <dependency>
           <groupId>junitgroupId>
           <artifactId>junitartifactId>
           <version>4.12version>
       dependency>
   
       <dependency>
           <groupId>mysqlgroupId>
           <artifactId>mysql-connector-javaartifactId>
           <version>5.1.47version>
       dependency>
   
       <dependency>
           <groupId>org.mybatisgroupId>
           <artifactId>mybatisartifactId>
           <version>3.5.7version>
       dependency>
   
       <dependency>
           <groupId>org.mybatisgroupId>
           <artifactId>mybatis-springartifactId>
           <version>2.0.6version>
       dependency>
   
       <dependency>
           <groupId>org.springframeworkgroupId>
           <artifactId>spring-webmvcartifactId>
           <version>5.2.12.RELEASEversion>
       dependency>
   
       <dependency>
           <groupId>org.springframeworkgroupId>
           <artifactId>spring-jdbcartifactId>
           <version>5.2.12.RELEASEversion>
       dependency>
   
       <dependency>
           <groupId>org.aspectjgroupId>
           <artifactId>aspectjweaverartifactId>
           <version>1.9.5version>
       dependency>
   
       <dependency>
           <groupId>org.projectlombokgroupId>
           <artifactId>lombokartifactId>
           <version>1.18.20version>
       dependency>
   
       <dependency>
           <groupId>log4jgroupId>
           <artifactId>log4jartifactId>
           <version>1.2.17version>
       dependency>
   dependencies>
   

2. 编写配置文件

3. 测试

MyBatis回顾

1. 编写实体类

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

2. 编写核心配置文件

   
   
   <configuration>
   
       <properties resource="db.properties"/>
       
       <settings>
           <setting name="logImpl" value="STDOUT_LOGGING"/>
       settings>
   
       <typeAliases>
           <package name="com.alb.pojo"/>
       typeAliases>
       
       <environments default="development">
           <environment id="development">
               <transactionManager type="JDBC"/>
               <dataSource type="POOLED">
                   <property name="username" value="${username}"/>
                   <property name="password" value="${password}"/>
                   <property name="url" value="${url}"/>
                   <property name="driver" value="${driver}"/>
               dataSource>
           environment>
       environments>
   
       <mappers>
           <mapper class="com.alb.mapper.UserMapper"/>
       mappers>
       
   configuration>
   

3. 编写接口

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

4. 编写Mapper.xml

   
   
   <mapper namespace="com.alb.mapper.UserMapper">
   
       <select id="selectAll" resultType="User">
           select * from user;
       select>
   
   mapper>
   

5. 测试

   public class MyTest {
       private SqlSessionFactory sqlSessionFactory;
       @Test
       public void test(){
           try {
               String resources = "mybatis-config.xml";
               InputStream is = Resources.getResourceAsStream(resources);
               sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
           } catch (IOException e) {
               e.printStackTrace();
           }
           SqlSession sqlSession = sqlSessionFactory.openSession(true);
   
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           List<User> userList = mapper.selectAll();
   
           for (User user : userList) {
               System.out.println(user);
           }
   
           sqlSession.close();
   
       }
   }
   

MyBatis-Spring

什么是MyBatis-Spring

MyBatis-Spring 会帮助你将 MyBatis 代码无缝地整合到 Spring 中。它将允许 MyBatis 参与到 Spring 的事务管理之中，创建映射器 mapper 和 SqlSession 并注入到 bean 中，以及将 Mybatis 的异常转换为 Spring 的 DataAccessException。 最终，可以做到应用代码不依赖于 MyBatis，Spring 或 MyBatis-Spring。

步骤：

1. 编写数据源配置

   
   <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
       <property name="username" value="root"/>
       <property name="password" value="111111"/>
       <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
       <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=UTF-8"/>
   bean>
   
   

2. sqlSessionFactory

   
   <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
       <property name="dataSource" ref="dataSource" />
       
       <property name="configLocation" value="classpath:mybatis-config.xml"/>
       <property name="mapperLocations" value="classpath:com/alb/mapper/*.xml"/>
   bean>
   

3. sqlSessionTemplate

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

4. 需要给接口加实现类

   public class UserMapperImpl implements UserMapper {
   
       private SqlSessionTemplate sqlSession;
   
       public void setSqlSession(SqlSessionTemplate sqlSession) {
           this.sqlSession = sqlSession;
       }
   
       @Override
       public List<User> selectAll() {
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
           return mapper.selectAll();
       }
   }
   

5. 将自己写的实现类，注入到Spring中

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

6. 测试使用即可

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

方式二：

​ 继承SqlSessionDaoSupport：

// 继承SqlSessionDaoSupport后，我们不需要自己去注入一个sqlSession，由该类的方法提供
public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper {
    @Override
    public List<User> selectAll() {
        return getSqlSession().getMapper(UserMapper.class).selectAll();
    }
}

​ 将该bean注册至spring容器中：

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

测试，与上方一样