Mybatis 用注解处理CRUD

傷城~ 2024-02-18 16:42 10阅读 0赞

修改config.xml文件：

UserMapper.java:

package com.dw.dao;
    
    import java.util.List;
    import java.util.Map;
    
    import org.apache.ibatis.annotations.Delete;
    import org.apache.ibatis.annotations.Insert;
    import org.apache.ibatis.annotations.Param;
    import org.apache.ibatis.annotations.Result;
    import org.apache.ibatis.annotations.ResultType;
    import org.apache.ibatis.annotations.Results;
    import org.apache.ibatis.annotations.Select;
    import org.apache.ibatis.annotations.Update;
    
    import com.dw.entity.User;
    
    public interface UserMapper {
      @Select("select * from user as u where u.id=#{id}") //数据表中的字段名与实体属性对应可以用这种方法，否则用下一种
      //@Select("select id,t_username as username,password from user as u where u.id = #{id}")
      @ResultType(User.class)  //可以不写
    	public User selectById(Integer id);
      
      @Select("select * from user")
      @Results({ //相当于resultMap ，这里也可以不写，当字段名与属性相同时
    	  @Result(property="username",column="username"),
    	  @Result(property="password",column="password")
      })
      public List<User> selectAll();
      
      //多参数查询
      //@Select("select id,username,password from user as u where u.id=#{0} and u.username=#{1}")
      @Select("select id,username,password from user as u where u.id=#{id} and u.username=#{name}")
      public User selectByMulParam(@Param("id")Integer id,@Param("name")String name);
    
      
      @Select("select id,username,password from user as u where u.id=#{a} and u.username=#{b}")
      public User selectByMap(Map<String, Object> mp);
      
      
      
      @Update("update user as u set u.password=#{pwd} where u.id=#{id}")
      public void updateById(@Param("id")Integer id,@Param("pwd")String pwd);
      
      @Update("update user as u set u.password=#{password} where u.id=#{id}")
      public void updateByUser(User user);
      
      
      @Insert("insert into user(username,password) values(#{username},#{password})")
      public void insertUser(User user);
      
      @Delete("delete from user where user.username = #{n}")
      public void delectUserByName(String name);
    }

测试：

/*
      * 注解配置
      */
     
      @Test
      public void testSelectById(){
    	  init();
    	  Integer id = 5;
    	  User user = userMapper.selectById(id);
    	  System.out.println(user);
    	  destory();
      }
    
      @Test
      public void testSelectAll(){
    	  init();
    	  List<User> list = userMapper.selectAll();
    	  for (User user : list) {
    		System.out.println(user);
    	}
    	  destory();
      }  
      
      @Test
      public void testSelectByMulParam(){
    	  init();
    	  Integer id = 5;
    	  String name = "李斯";
    	  User user = userMapper.selectByMulParam(id, name);
    	  System.out.println(user);
    	  destory();
      } 
      
      @Test
      public void testSelectByMap(){
    	  init();
    	  Map<String, Object> mp = new HashMap<>();
    	  mp.put("a", 5);
    	  mp.put("b", "李斯");
    	  User user = userMapper.selectByMap(mp);
    	  System.out.println(user);
    	  destory();
      } 
      
      
      @Test
      public void testUpdateById(){
    	  init();
          Integer id = 5;
          String pwd = "hahaha";
    	  userMapper.updateById(id, pwd);
    	  destory();
      }   
      
      @Test
      public void testUpdateByUser(){
    	  init();
          User user = new User();
          user.setId(5);
          user.setPassword("heihei");
    	  userMapper.updateByUser(user);
    	  destory();
      }  
      
      
      @Test
      public void testInsertUser(){
    	  init();
          User user = new User();
          user.setUsername("zhoujielun");
          user.setPassword("123456");
    	  userMapper.insertUser(user);
    	  destory();
      }  
      
      @Test
      public void testDelectUser(){
    	  init();
    	  userMapper.delectUserByName("zhoujielun");
    	  destory();
      }  
      
    	private void init(){
    		try {
    			inputStream = Resources.getResourceAsStream("config.xml");
    			sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    			session = sessionFactory.openSession();
    			//userDao = session.getMapper(UserDao.class);
    			userMapper = session.getMapper(UserMapper.class);
    		} catch (IOException e) {
    			e.printStackTrace();
    		}
    	}
    	
    	private void destory(){
    		if(session != null){
    			session.close();
    		}
    		if(inputStream != null){
    			try {
    				inputStream.close();
    			} catch (IOException e) {
    				e.printStackTrace();
    			}
    		}
    	}