mybatis传参

mybatis的参数传入
测试代码

 @Test
    public void select_all() throws IOException {
        try (SqlSession sqlSession = MybatisUtil.createSqlsession()) {
            UserMapper mapper = sqlSession.getMapper(UserMapper.class);
//            pojo对象作为参数
//            User user = new User();
//            user.setUserName("张");
//            for (User user1 : mapper.selectbyuser(user) ) {
//                System.out.println(user1.getUserName());
//            }
//----------------------------------------------------------------------------------
//				map传参
//            Map<String,String> usermap = new HashMap<String,String>();
//            usermap.put("userName","张");
//            for (User user1 : mapper.selectbymap(usermap) ) {
//                System.out.println(user1.getUserName());
//            }

//-----------------------------------------------------------------------------------
//
//            单独传参
//            String userName = new String("张");
//            for (User user1 : mapper.selectbyparam(userName) ) {
//                System.out.println(user1.getUserName());
//            }
//        }
//        @Param注解 使用时xml文件中不需要paramType，单的参数可以不加注解
            String userName = new String("张");
            String userPassword = new String("123456");
            for (User user1 : mapper.selectnyannot(userName, userPassword)) {
                System.out.println(user1.getUserName());
            }


        }
    }

mapper接口

public interface UserMapper {
    public List<User> selectbyuser(User user);
    public List<User> selectbymap(Map<String,String> usermap);
    public List<User> selectbyparam(String userName);
    public List<User> selectnyannot(@Param("userName") String username,@Param("userPassword") String password);
}

mapper.xml文件

<?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.wj.dao.mapper.UserMapper">
<select id="selectbyuser" resultType="com.wj.dao.pojo.User">
select * from tb_user where userName like concat('%',#{userName},'%')
</select>
<select id="selectbymap" resultType="com.wj.dao.pojo.User" parameterType="Map">
select * from tb_user where userName like concat('%',#{userName},'%')
</select>
<select id="selectbyparam" resultType="com.wj.dao.pojo.User" parameterType="String">
select * from tb_user where userName like concat('%',#{userName},'%')
</select>
<select id="selectnyannot" resultType="com.wj.dao.pojo.User">
select * from tb_user where userName like concat('%',#{userName},'%') and userPassword = #{userPassword}
</select>
</mapper>
![在这里插入图片描述](https://img-blog.csdnimg.cn/ff4690f5d7534bb0b564929dc3d18edf.jpeg#pic_center)