mybatis和spring的整合

7.1、Mybatis步骤

1. 编写实体类

   public class User {
    
       private String userCode;
       private String userName;
       private String phone;
       private String address;
    
       public User() {
       }
    
       public User(String userCode, String userName, String phone, String address) {
           this.userCode = userCode;
           this.userName = userName;
           this.phone = phone;
           this.address = address;
       }
    
       public String getUserCode() {
           return userCode;
       }
    
       public void setUserCode(String userCode) {
           this.userCode = userCode;
       }
    
       public String getUserName() {
           return userName;
       }
    
       public void setUserName(String userName) {
           this.userName = userName;
       }
    
       public String getPhone() {
           return phone;
       }
    
       public void setPhone(String phone) {
           this.phone = phone;
       }
    
       public String getAddress() {
           return address;
       }
    
       public void setAddress(String address) {
           this.address = address;
       }
    
       @Override
       public String toString() {
           return "User{" +
                   "userCode='" + userCode + '\'' +
                   ", usrName='" + userName + '\'' +
                   ", phone='" + phone + '\'' +
                   ", address='" + address + '\'' +
                   '}';
       }
   }

2. 编写核心配置文件

   <?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>
       <properties resource="jdbc.properties"/>
    
       <settings>
           <setting name="logImpl" value="STDOUT_LOGGING"/>
           <setting name="mapUnderscoreToCamelCase" value="true"/>
           <setting name="cacheEnabled" value="true"/>
       </settings>
    
       <typeAliases>
           <typeAlias type="com.mhy.pojo.User" alias="user"/>
       </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.mhy.mapper.UserMapper"/>
       </mappers>
    
   </configuration>

3. 编写接口

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

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.mhy.mapper.UserMapper">
       <select id="queryAllUser" resultType="user">
           select user_code,user_name,phone,address from t_user;
       </select>
   </mapper>

5. 测试

   public class UserMapperTest {
    
       @Test
       public void queryAllUser() throws IOException {
           String resource = "mybatis-config.xml";
    
           InputStream inputStream = Resources.getResourceAsStream(resource);
    
           SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    
           SqlSession sqlSession = sessionFactory.openSession();
    
           UserMapper mapper = sqlSession.getMapper(UserMapper.class);
    
           List<User> users = mapper.queryAllUser();
    
           for (User user : users) {
               System.out.println(user);
           }
    
       }
    
   }

7.2、mybatis和spring的整合

7.2.1、方式一

1. 创建spring的xml文件

2. 编写数据源

       <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
           <property name="url" value="jdbc:mysql://localhost:3306/commodity?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
           <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
           <property name="username" value="root"/>
           <property name="password" value="123456"/>
       </bean>

3. 编写 SqlSessionFactoryBean的注入数据源和管理mybatis.xml

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

4. 编写SqlSessionTemplate来获取sqlSession来获取Mapper操作数据库

       <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
   <!--        使用构造器注入sessionFactory,因为没有set方法-->
           <constructor-arg index="0" ref="sessionFactory"/>
       </bean>

5. 需要给Mapper接口加实现类并在没有spring中注册

   public class UserMapperImpl implements UserMapper {
       private SqlSessionTemplate sqlSessionTemplate;
       public void setSqlSessionTemplate(SqlSessionTemplate sqlSessionTemplate) {
           this.sqlSessionTemplate = sqlSessionTemplate;
       }
       
       @Override
       public List<User> queryAllUser() {
           return sqlSessionTemplate.getMapper(UserMapper.class).queryAllUser();
       }
   }

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

7.2.2、方式二

1. 前三步与方式一一样

2. Impl类需要继承SqlSessionDaoSupport并实现Mapper接口

3. 然后set注入sessionFactory就可以了（这里使用的注解Autowired和Qualifier自动装配的）

   @Repository(value = "userMapperImpl2")
   public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper {
    
       @Autowired
       @Qualifier(value = "sessionFactory")
       @Override
       public void setSqlSessionFactory(SqlSessionFactory sqlSessionFactory) {
           super.setSqlSessionFactory(sqlSessionFactory);
       }
    
       @Override
       public List<User> queryAllUser() {
           return getSqlSession().getMapper(UserMapper.class).queryAllUser();
       }
   }