springboot项目中使用原生jdbc连接MySQL数据库

第一步：pom.xml中添加依赖；

[code]		<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>

第二步：编写连接类

[code]package com.example.demo.controller;
import java.lang.*;
import java.sql.*;

public class JDBCDemo {
public static void main(String[] args) throws SQLException, ClassNotFoundException {
//      Class.forName("com.mysql.jdbc.Driver");
Class.forName("com.mysql.cj.jdbc.Driver");
String url = "jdbc:mysql://127.0.0.1:3306/mysql?serverTimezone=GMT%2B8";
//      String url = "jdbc:mysql://127.0.0.1:3306/mysql";
Connection con = DriverManager.getConnection(url, "root", "123");
Statement statement = con.createStatement();
ResultSet resultSet = statement.executeQuery("select * from db");
while(resultSet.next()){
System.out.println(resultSet.getString(1));
}
}
}

执行结果：

注：问题记录

1.数据库密码错误会报错“Exception in thread "main" java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)”

2.url中未加参数‘serverTimezone=GMT%2B8’，会报下面的错误；

3.mysql驱动，使用

[code]"com.mysql.jdbc.Driver"

会报如下警告：

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

换成

[code]"com.mysql.cj.jdbc.Driver"

即可