SpringBoot系列：使用原生JDBC实现对数据库的增删改查

application.yml

spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
    driver-class-name: com.mysql.cj.jdbc.Driver

ApplicationTests

package com.xiao;

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;

@SpringBootTest
class Springboot04DataApplicationTests {

    @Autowired
    DataSource dataSource;

    @Test
    void contextLoads() {

        System.out.println(dataSource.getClass());
        //获得数据库链接
        try {
            Connection connection= dataSource.getConnection();
            System.out.println(connection);
            connection.close();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }

    }

}

JDBCController

package com.xiao.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;
import java.util.Map;

@RestController
public class JDBCController {

    @Autowired
    JdbcTemplate jdbcTemplate;

    @GetMapping("/userList")
    public List<Map<String,Object>> userList(){
        String sql="select * from user";
        List<Map<String,Object>> list_maps=jdbcTemplate.queryForList(sql);
        return list_maps;
    }

    @GetMapping("/addUser")
    public String addUser(){
        String sql="insert into mybatis.user(id,name,pwd) values(4,'小如','123456')";
        jdbcTemplate.update(sql);
        return "ok";
    }

    @GetMapping("/updateUser/{id}")
    public String updateUser(@PathVariable("id") int id){
        String sql="update mybatis.user set name=?,pwd=? where id="+id;
        Object[] objects=new Object[2];
        objects[0]="小品";
        objects[1]="3745678";
        jdbcTemplate.update(sql,objects);
        return "ok";
    }

    @GetMapping("/deleteUser/{id}")
    public String deleteUser(@PathVariable("id") int id){
        String sql="delete from mybatis.user where id=?";
        jdbcTemplate.update(sql,id);
        return "ok";
    }
}

使用springboot后，你会发现，即便是原生JDBC来进行CRUD，依然十分的简便，因为springboot帮我们做了很多事，一个DataSource，一个JdbcTemplate就省去了很多很多我们原先需要做的事了。