万能的map

User接口类

在接口方法中，参数直接传递Map；

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

mapper配置文件

编写sql语句的时候，需要传递参数类型，参数类型为map

    <insert id="addUser" parameterType="map">
       insert into user.user(username, password, phone, qqnumber) VALUES (#{userid},#{pw},#{phon},#{qq});
   </insert>

test测试方法

在使用方法的时候，Map的 key 为 sql中取的值即可，没有顺序要求！

    @Test
    public void testaddUser2(){
        SqlSession sqlSession = mybatisUtil.getsqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        Map<String,Object>map = new HashMap<String, Object>();
        map.put("userid",5);
        map.put("pw","sdad");
        map.put("phon",2143412341);
        map.put("qq",149812701);
        mapper.addUser2(map);
        sqlSession.close();
    }

• 总结：如果参数过多，我们可以考虑直接使用Map实现，如果参数比较少，直接传递参数即可

模糊查询

    List<User> getUSerlike(String username);

方法一（在Java代码中添加sql通配符）

    <select id="getUserList" resultType="com.mybatis.pojo.User">
        select * from user.user where name like #{username};
    </select>

    @Test
    public void testlikeList(){
        SqlSession sqlSession = mybatisUtil.getsqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        mapper.getUSerlike("%李%");
        List<User> userList = mapper.getUserList();
        for (User user:userList){
            System.out.println(user);
        }
        //关闭sqlsession
        sqlSession.close();
    }

方法二（在sql语句中拼接通配符，会引起sql注入）

    <select id="getUserList" resultType="com.mybatis.pojo.User">
        select * from foo where bar like "%"#{value}"%"
    </select>

    @Test
    public void testlikeList(){
        SqlSession sqlSession = mybatisUtil.getsqlSession();
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        mapper.getUSerlike("李");
        List<User> userList = mapper.getUserList();
        for (User user:userList){
            System.out.println(user);
        }
        //关闭sqlsession
        sqlSession.close();
    }