(1)DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver()) —> 反射注册Class.forName(“com.mysql.cj.jdbc.Driver”)
package com.jdbc;
import java.sql.*;
public class JDBCTest03 {
public static void main(String[] args) {
try{
//1.注册驱动
//注册驱动的第二种方法:常用
Class.forName("com.mysql.cj.jdbc.Driver");//这个异常对应第一个catch语句块
//2.获取连接
//这个异常对应第二个catch语句块SQLException
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/bjpowernode?serverTimezone=GMT%2B8","root","jh7851192");
System.out.println(conn);//com.mysql.cj.jdbc.ConnectionImpl@1cbbffcd
}catch (ClassNotFoundException e){
e.printStackTrace();
}catch(SQLException e){
e.printStackTrace();
}
}
}
(2)使用配置文件properties获取连接,进行delete/update
//配置文件properties
driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/bjpowernode?serverTimezone=GMT%2B8
user=root
password=jh7851192
package com.jdbc;
/**
将连接数据库的所有信息配置到配置文件中
* */
import java.util.*;
import java.sql.*;
public class JDBCTest04 {
public static void main(String[] args) {
//使用资源绑定器绑定属性配置文件
ResourceBundle bundle=ResourceBundle.getBundle("jdbc");
String driver =bundle.getString("driver");
String url =bundle.getString("url");
String user =bundle.getString("user");
String password =bundle.getString("password");
Connection conn02=null;
Statement stmt02=null;
try{
//1,。注册驱动
Class.forName(driver);
//2.获取连接
conn02=DriverManager.getConnection(url,user,password);
//3.获取数据库操作对象
stmt02=conn02.createStatement();
//4.ִ执行SQL语句
//String sql02="delete from dept where deptno=109";
String sql02="update dept set dname='销售部',loc='德国' where deptno=112";
int count=stmt02.executeUpdate(sql02);
System.out.println(count==1?"删除成功":"删除失败");
}catch(Exception e){
e.printStackTrace();
}finally {
//6.释放资源
if(stmt02!=null){
try{
stmt02.close();
}catch (SQLException e){
e.printStackTrace();
}
}
if(conn02!=null){
try{
conn02.close();
}catch (SQLException e){
e.printStackTrace();
}
}
}
}
}
结果:String sql02=“update dept set dname=‘销售部’,loc=‘德国’ where deptno=112”;