mybatis增删改查.mdx

id	title
Mybatis增删改查	3. Mybatis增删改查

接口代码：

和之前操作数据库dao层接口是一样的

package com.neu.dao;

import com.neu.pojo.User;

import java.util.List;

public interface UserMapper {

    /**
     * 查询所有User
     * @return List<User>
     */
    List<User> getUserList();

    /**
     * 通过id查询User
     * @param id
     * @return int
     */
    User getUserById(int id);

    /**
     * 插入User
     * @param user
     * @return int
     */
    int addUser(User user);

    /**
     * 修改User
     * @param user
     * @return int
     */
    int updateUser(User user);

    /**
     * 通过id删除User
     * @param id
     * @return int
     */
    int deleteUser(int id);
}

UserMapper.xml

<?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">

<!--namespace绑定UserDao/UserMapper-->
<mapper namespace="com.neu.dao.UserMapper">
    <!--select id="绑定的dao接口中的方法名"-->
    <select id="getUserList" resultType="com.neu.pojo.User">
        select * from user
    </select>

    <!--通过id查询-->
    <select id="getUserById" parameterType="int" resultType="com.neu.pojo.User">
        select * from user where id = #{id}
    </select>

    <!--增-->
    <insert id="addUser" parameterType="com.neu.pojo.User">
        insert into user values (#{id},#{name},#{pwd})
    </insert>

    <!--改-->
    <update id="updateUser" parameterType="com.neu.pojo.User">
        update user set name = #{name} ,pwd = #{pwd} where id = #{id}
    </update>

    <!--删-->
    <delete id="deleteUser" parameterType="int">
        delete from user where id = #{id}
    </delete>
</mapper>

测试代码：