Mybatis实现CRUD | 易学教程

准备工作

CRUD

增
dao接口：public boolean addUser(User user);
dao中.xml映射

<insert id="addUser" parameterType="cn.edu.hbue.wmp.entity.User">
        insert into mybatis.user(id, userName, pwd) values(#{id},#{userName},#{pwd})
    </insert>

也可以改为如下，只是在配置文件中要加入<typeAliases> 起别名

<insert id="addUser" parameterType="User">
        insert into mybatis.user(id, userName, pwd) values(#{id},#{userName},#{pwd})
    </insert>

注意:增删改在测试时要提交事务

 @Test
    public void addUserTest(){


        //1.获取sqlSession对象
        SqlSession sqlSession = MybatisUtil.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = new User(11,"小刘","123456");
        userMapper.addUser(user);
        //提交事务
        sqlSession.commit();
        //关闭sqlSession
        sqlSession.close();


    }

<delete id="deleteUser" parameterType="int">
        delete from mybatis.user where id = #{id}
    </delete>

 <update id="updateUser" parameterType="cn.edu.hbue.wmp.entity.User">
        update mybatis.user
        set userName = #{userName},pwd = #{pwd}
        where id = #{id};
    </update>

查
普通查询：见上篇文章：mybatis入门
模糊查询：

接口


    //模糊查询
    List<User> getUserLike(String value);

xml映射

 <select id="getUserLike" resultType="User">
        select * from mybatis.user where userName like #{value}
    </select>

测试类

 List<User> user = userMapper.getUserLike("%刘%");

万能map

假设，我们的实体类，或者数据库中的表，字段或者参数过多，我们应当考虑使用Map！

boolean addUser2(Map<String,Object> map);

 <!--对象中的属性，可以直接取出来    传递map的key-->
    <insert id="addUser" parameterType="map">
        insert into mybatis.user (id, pwd) values (#{userid},#{passWord});
    </insert>

 Map<String, Object> map = new HashMap<String, Object>();

        map.put("userid",5);
        map.put("passWord","2222333");

        mapper.addUser2(map);

来源：oschina

链接：https://my.oschina.net/u/4314362/blog/4360004

标签

MyBatis