mybatis使用注解完成简单的增删改查源码含测试方法

注解可以拿来写简单的sql语句，但是复杂的sql语句建议还是使用xml的方式来实现

数据库：





DAO层

package com.kuang.dao;

import com.kuang.pojo.User;
import org.apache.ibatis.annotations.*;

import java.util.List;
import java.util.Map;

public interface UserMapper {

    @Select(" select * from  mybatis.user")
    public  List getUserList();

    @Select("select * from user where id=#{id}")
    public User getUserById(@Param("id") int id,@Param("name") String name);

    @Insert("insert into user(name,pwd) value(#{name},#{pwd})")
    int addUser(User user);

    @Update("update mybatis.user set name=#{name},pwd=#{pwd} where id=#{id}")
    int updateUser(User user);

    @Delete("delete from mybatis.user where id=#{id}")
    int deleteUser(User user);
}

方法getUserById上面那个SQL语句是取的参数取的是前面那个@Param里的参数，建议多个基本类型的参数都在前面加一个@Param

测试方法代码

package dao;

import com.alibaba.fastjson.JSON;
import com.kuang.dao.UserMapper;
import com.kuang.pojo.User;
import com.kuang.util.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import java.util.List;

public class UserDaoTest {


    @Test
    public  void addUser(){
        SqlSession sqlSession=null;
        try {
            sqlSession= MybatisUtils.getSqlSession();
            UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
            User user=new User();
            user.setId(13);
            userMapper.deleteUser(user);
            List list=userMapper.getUserList();
            for (User user1:list){
                System.out.println(JSON.toJSONString(user1));
            }

        }catch (Exception e){

        }finally {

        }
    }

    @Test
    public  void deleteUser(){
        SqlSession sqlSession=null;
        try {
            sqlSession= MybatisUtils.getSqlSession();
            UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
            User user=new User();
            user.setName("ohaode");
            user.setPwd("2222");
            user.setId(13);
            userMapper.deleteUser(user);
            List list=userMapper.getUserList();
            for (User user1:list){
                System.out.println(JSON.toJSONString(user1));
            }

        }catch (Exception e){

        }finally {

        }
    }


    @Test
    public  void updateUser(){
        SqlSession sqlSession=null;
        try {
            sqlSession= MybatisUtils.getSqlSession();
            UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
            User user=new User();
            user.setName("测试");
            user.setPwd("2860");
            userMapper.addUser(user);
            List list=userMapper.getUserList();
            for (User user1:list){
                System.out.println(JSON.toJSONString(user1));
            }

        }catch (Exception e){

        }finally {

        }
    }


    @Test
    public  void getUserList(){
        SqlSession sqlSession=null;
        try {
            sqlSession= MybatisUtils.getSqlSession();
            UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
            ListuserList= userMapper.getUserList();
            for (User user:userList){
                System.out.println(JSON.toJSONString(user));
            }
        }catch (Exception e){

        }finally {

        }
    }

}

使用注解时就不用在xml里写方法了，然后再核心配置文件里需要把mapper写到自己要面向的dao接口那了，而不是之前的xml文件

现在

之前