MySQL 的JDBC操作一般步骤

package com.laili.connect;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class ConnectTest{public static void main(String[] args){String connStr = "jdbc:mysql://localhost:3306/testdb";Connection conn = null;Statement stmt = null;try{//数据库访问的一般步骤：//1.获得连接conn = DriverManager.getConnection(connStr, "root", "7683358");System.out.println(conn);//2.使用连接创建语句对象stmt = conn.createStatement();//3.使用语句对象执行查询等操作ResultSet set = stmt.executeQuery("select * from customers;");//遍历结果集while(set.next()){int id = set.getInt("id");String name = set.getString("name");int age = set.getInt("age");String address = set.getString("address");float salary = set.getFloat("salary");System.out.println(id + " " + name + " " + age + " " + address + " " + salary);}}catch (Exception e){e.printStackTrace();}finally{if(stmt != null){try{System.out.println("query statement closed!");stmt.close();}catch (SQLException e){e.printStackTrace();}stmt = null;}if(conn != null){try{System.out.println("connction closed!");conn.close();}catch (SQLException e){e.printStackTrace();}conn = null;}}}}