三、MyBaits增删改查

1. UserMapper接口

public interface UserMapper {

    public List<User> getList();

    public User getById(Integer id);

    public Integer insertOne(User user);

    public Integer updateById(User user);

    public Integer deleteById(Integer id);
}

 

2. UserMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.zx.mapper.UserMapper">
    <select id="getList" resultType="User">
        select * from `user`;
    </select>

    <select id="getById" parameterType="int" resultType="User">
        select * from `user` where id = #{id};
    </select>

    <insert id="insertOne" parameterType="User">
        insert into `user`(name,pwd) values (#{name},#{pwd});
    </insert>

    <update id="updateById" parameterType="User">
        update `user` set name=#{name},pwd=#{pwd} where id = #{id};
    </update>

    <delete id="deleteById" parameterType="int">
        delete from `user` where id = #{id};
    </delete>

</mapper>

 

 3. 测试类

public class UserTest {

    @Test
    public void getList(){
        SqlSession sqlSession = MyBaitsUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        List<User> list = userMapper.getList();
        for (User user : list) {
            System.out.println(user);
        }
        sqlSession.close();
    }

    @Test
    public void getById(){
        SqlSession sqlSession = MyBaitsUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = userMapper.getById(1);
        System.out.println(user);
        sqlSession.close();
    }

    @Test
    public void insertOne(){
        SqlSession sqlSession = MyBaitsUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = new User();
        user.setName("zl");
        user.setPwd("654321");
        Integer row = userMapper.insertOne(user);
        if (row > 0) {
            System.out.println("插入成功");
        }
        //必须提交事务
        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void updateById(){
        SqlSession sqlSession = MyBaitsUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        Integer row = userMapper.updateById(new User(4,"z6","123456"));
        if (row > 0) {
            System.out.println("修改成功");
        }
        //必须提交事务
        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void deleteById(){
        SqlSession sqlSession = MyBaitsUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        Integer row = userMapper.deleteById(4);
        if (row > 0) {
            System.out.println("删除成功");
        }
        //必须提交事务
        sqlSession.commit();
        sqlSession.close();
    }
}