mybatis自動生成mapper,DAO,對應的關系

1.DAO

package com.rinlink.intelligent.DAO;

import com.rinlink.intelligent.entity.User;

public interface UserMapper {
    int deleteByPrimaryKey(Integer id);

    int insert(User record);

    int insertSelective(User record);

    User selectByPrimaryKey(Integer id);

    int updateByPrimaryKeySelective(User record);

    int updateByPrimaryKey(User record);
}
           

2.mapper

<?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.rinlink.intelligent.DAO.UserMapper">
  <resultMap id="BaseResultMap" type="com.rinlink.intelligent.entity.User">
    <id column="id" jdbcType="INTEGER" property="id" />
    <result column="user_name" jdbcType="VARCHAR" property="userName" />
    <result column="password" jdbcType="VARCHAR" property="password" />
    <result column="age" jdbcType="INTEGER" property="age" />
  </resultMap>
  <sql id="Base_Column_List">
    id, user_name, password, age
  </sql>
  <select id="selectByPrimaryKey" parameterType="java.lang.Integer" resultMap="BaseResultMap">
    select 
    <include refid="Base_Column_List" />
    from user_t
    where id = #{id,jdbcType=INTEGER}
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
    delete from user_t
    where id = #{id,jdbcType=INTEGER}
  </delete>
  <insert id="insert" parameterType="com.rinlink.intelligent.entity.User">
    insert into user_t (id, user_name, password, 
      age)
    values (#{id,jdbcType=INTEGER}, #{userName,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}, 
      #{age,jdbcType=INTEGER})
  </insert>
  <insert id="insertSelective" parameterType="com.rinlink.intelligent.entity.User">
    insert into user_t
    <trim prefix="(" suffix=")" suffixOverrides=",">
      <if test="id != null">
        id,
      </if>
      <if test="userName != null">
        user_name,
      </if>
      <if test="password != null">
        password,
      </if>
      <if test="age != null">
        age,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides=",">
      <if test="id != null">
        #{id,jdbcType=INTEGER},
      </if>
      <if test="userName != null">
        #{userName,jdbcType=VARCHAR},
      </if>
      <if test="password != null">
        #{password,jdbcType=VARCHAR},
      </if>
      <if test="age != null">
        #{age,jdbcType=INTEGER},
      </if>
    </trim>
  </insert>
  <update id="updateByPrimaryKeySelective" parameterType="com.rinlink.intelligent.entity.User">
    update user_t
    <set>
      <if test="userName != null">
        user_name = #{userName,jdbcType=VARCHAR},
      </if>
      <if test="password != null">
        password = #{password,jdbcType=VARCHAR},
      </if>
      <if test="age != null">
        age = #{age,jdbcType=INTEGER},
      </if>
    </set>
    where id = #{id,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="com.rinlink.intelligent.entity.User">
    update user_t
    set user_name = #{userName,jdbcType=VARCHAR},
      password = #{password,jdbcType=VARCHAR},
      age = #{age,jdbcType=INTEGER}
    where id = #{id,jdbcType=INTEGER}
  </update>
</mapper>
           

關系：

類路徑+方法名==命名空間+對應ID

例如：

類路徑：com.rinlink.intelligent.DAO.UserMapper

方法名：updateByPrimaryKey

mapper的命名空間： com.rinlink.intelligent.DAO.UserMapper

mapper的ID：updateByPrimaryKey