转载

Mybatis学习笔记 2：Mybatis 基本的CURD操作

Mybatis把访问数据库的操作都封装起来了，所以当我们使用Mybatis进行数据库操作时，只需要提供SQL语句就可以了，代码的逻辑会变得非常清晰，书写起来也很简洁。

下面的例子都是基于上一篇文章

完整代码在这

一、create操作

在user.xml文件中添加

<insert id="addUser" parameterType="User">
		insert into user (user_name, user_id, user_pwd, user_phone) values(#{user_name}, #{user_id}, #{user_pwd}, #{user_phone} )
	</insert>
复制代码

代码中添加：

User user = new User();
user.setUser_name("Eve");
user.setUser_id("12345");
user.setUser_phone("13978992134");
user.setUser_pwd("1111111");
session.insert("addUser", user);
session.commit();
session.close();
复制代码

二、算了，CURD没啥好写的，把代码贴在这吧

user.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">

<mapper namespace="com.learn.pojo">
    <select id="listUser" resultType="User">
	        select * from   user
	</select>

	<insert id="addUser" parameterType="User">
		insert into user (user_name, user_id, user_pwd, user_phone) values(#{user_name}, #{user_id}, #{user_pwd}, #{user_phone} )
	</insert>

	<delete id="deleteUser" parameterType="User" >
            delete from user where user_id= #{user_id}
    </delete>

	<select id="getUser" parameterType="String" resultType="User">
            select * from user where id= #{user_id}
        </select>

	<update id="updateUser" parameterType="User" >
            update user set name=#{user_name} where id=#{user_id}
        </update>
</mapper>
复制代码

Test.java

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import com.learn.pojo.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class Test {

    public static void main(String[] args) throws IOException {
        //声明配置文件地址
        String resource = "mybatis-config.xml";
        //得到输入流
        InputStream inputStream = Resources.getResourceAsStream(resource);
        //创建sql会话工厂
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        //打开sql会话
        SqlSession session = sqlSessionFactory.openSession();
        //获取查询结果
        List<User> lu = session.selectList("listUser");
        for (User u : lu) {
            System.out.println(u.getUser_name());
            System.out.println(u.getUser_id());
            System.out.println(u.getUser_phone());
            System.out.println("------------------------");


        }

        //创建User对象
        User user = new User();
        user.setUser_name("Eve");
        user.setUser_id("12345");
        user.setUser_phone("13978992134");
        user.setUser_pwd("1111111");

        //插入记录
        session.insert("addUser", user);
        //删除记录
        session.delete("deleteUser", user);
        //根据id选记录
        User newUserr = session.selectOne("getUser","10086");

        //更新记录
        user.setUser_name("改过名的Eve");
        session.update("updateUser",user);

        session.commit();
        session.close();

    }

}
复制代码

原文 https://juejin.im/post/5c652d32f265da2dd05229d6

正文到此结束