UserMapper.xml

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

    <resultMap type="user" id="userList">
        <!-- type为返回列表元素的类全名或别名 -->
        <result column="username" property="username"/>
        <result column="password" property="password"/>
        <result column="enabled" property="enabled"/>
        <result column="context" property="context"
                typeHandler="com.Config.MyTypeHandler"/>
    </resultMap>


    <insert id="insert" parameterType="user">
    insert into users(username,
    password,enabled,context) values(#{username}, #{password},#{enabled},#{context})
  </insert>
    <select id="selectUser" parameterType="String" resultType="user">
    SELECT * FROM users WHERE username = #{username}
  </select>
    <select id="selectAll" resultMap="userList">
    SELECT * FROM users
  </select>
</mapper>