点餐系统源代码，基于数据库和java

package zuihou; import java.util.Scanner; //import com.mysql.jdbc.PreparedStatement; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class czuihou { static String url="jdbc:mysql://localhost:3306/fastfood?characterEncoding=UTF-8&serverTimezone=GMT%2B8&useSSL=true"; static String user="root"; static String password="123456"; public static void main(String[] arges) throws Exception { Connection conn = null; //加载驱动程序 try { //Class.forName("com.mysql.cj.jdbc.Driver"); //Connection conn =DriverManager.getConnection(url="jdbc:mysql://localhost:3306/fastfood?characterEncoding=UTF-8&serverTimezone=GMT%2B8&useSSL=true",user="root",password="123456"); conn=JDBCUtils.getConnection(); } catch (Exception e) { e.printStackTrace(); } //denglu(); System.out.print(" ****欢迎使用华杏儿订餐系统************* \n"); System.out.print(" 请选择您的身份 \n"); System.out.print(" ******1.员工**************\n"); System.out.print(" ******2.客人**************\n"); System.out.print(" ******3.退出登录*********** \n"); Scanner input = new Scanner(System.in); int a = input.nextInt(); switch(a) { case 1: System.out.println("********员工登录**********"); user2(); System.out.print(" ********请查看员工信息表********* \n"); yuangong3(); break; case 2: System.out.println("********客人点餐服务*********"); System.out.println("请输入客户姓名和客人人数"); Scanner string = new Scanner(System.in); String kname = string.next(); //Scanner input = new Scanner(System.in); int knumber = string.nextInt(); //2.创建statement类对象，用来执行SQL语句 keren1(kname,knumber); menu(); break; case 3:System.out.println("谢谢使用，欢迎下次光临！");break; }} private static void user2() { // TODO Auto-generated method stub //1.键盘录入，接受用户名和密码 Scanner sc = new Scanner(System.in); System.out.println("请输入用户名："); String username = sc.nextLine(); System.out.println("请输入密码："); String password = sc.nextLine(); //2.调用方法 boolean flag = new czuihou().login(username, password); //3.判断结果，输出不同语句 if(flag){ //登录成功 System.out.println("登录成功！"); }else{ System.out.println("用户名或密码错误！"); } } private static void keren1(String kname,int knumber) { // TODO Auto-generated method stub Statement statement = null; Connection conn = null; try { conn = JDBCUtils.getConnection(); statement = conn.createStatement(); PreparedStatement pst = conn.prepareStatement("insert into keren1 (kname,knumber) values(?,?)"); //int a = statement.executeUpdate(sql); //System.out.println(a); pst.setString(1,kname);//这里也是1对应第一个问号，几个问号有几个 pst.setInt(2, knumber); pst.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } /** * @throws SQLException * */ @SuppressWarnings("unused") private static void menu() throws SQLException { // TODO Auto-generated method stub System.out.print(" \n"); System.out.print(" *********************************** \n"); System.out.print(" 请选择服务类型 \n"); System.out.print(" 1.我要订餐 \n"); System.out.print(" 2.查看订单 \n"); System.out.print(" 3.修改订单 \n"); System.out.print(" 4.删除订单 \n"); System.out.print(" 5.退出 \n"); System.out.print(" ************************************ \n"); @SuppressWarnings("resource") Scanner input = new Scanner(System.in); int n = input.nextInt(); switch(n) { case 1: System.out.println("************我要订餐************"); System.out.println("您可以选择下列的菜品："); try { chacaipin1(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("请您选择菜品的编号："); String a12 = input.next(); System.out.println("请您选择菜品的名字："); String a13 = input.next(); System.out.println("请您选择菜品的数量："); int amount = input.nextInt(); System.out.println("请您确认菜品的价格："); String price = input.next(); System.out.println("餐桌情况："); chazhuo4(); System.out.println("请选择餐桌号："); int zno1=input.nextInt(); insert(a12,a13,amount,price,zno1); settlement(); break; case 2: System.out.println("************您的订单************"); try { dingdan(); }catch (Exception e) { e.printStackTrace(); } break; case 3: System.out.println("***********修改订单***********"); try { System.out.println("********本店菜品**********"); chacaipin1(); System.out.println("********您的订单**********"); dingdan(); }catch (Exception e) { e.printStackTrace(); } System.out.println("请输入订单编号："); String ono = input.next(); System.out.println("您要改成的菜品是："); String oname = input.next(); System.out.println("您要改成的点餐份数是："); int amount1= input.nextInt(); System.out.println("您要改成的桌号是："); int zhuono = input.nextInt(); //insert(a14,a15,amount1); update( ono,oname,amount1,zhuono ); break; case 4: System.out.println("*******您的订单*********"); try { dingdan(); }catch (Exception e) { e.printStackTrace(); } System.out.print("请您选择要删除的订单编号："); String ono1 = input.next(); deletedingdan(ono1); break; case 5: System.out.println("谢谢使用，欢迎下次光临！");break; default: System.out.print(" \n 您输入有误，请按任意键重新选择 \n"); } } private static void yuangong3() throws SQLException { // TODO Auto-generated method stub Connection con = null; con = JDBCUtils.getConnection(); Statement stmt = con.createStatement(); ResultSet fm = ( stmt.executeQuery("select * from yuangong")); System.out.println("员工编号"+"\t"+"员工姓名"+"\t"+"员工类型"+"\t"+"员工手机号"); while(fm.next()){ System.out.println(fm.getInt(1)+"\t"+fm.getString(2)+"\t"+fm.getString(3)+"\t"+fm.getString(4)); } System.out.println("----------------------------------------------"); } private static void settlement() throws SQLException { // TODO Auto-generated method stub //加载数据库驱动 Connection con = null; con = JDBCUtils.getConnection(); System.out.println("请输入订单编号"); @SuppressWarnings("resource") Scanner input = new Scanner(System.in); String n = input.next(); Statement statement = null; statement = con.createStatement(); String sql = "select price from dingdan where ono="+n+";"; ResultSet rs =statement.executeQuery(sql); while(rs.next()){ //获取Price这列数据 String price = rs.getString("price"); //输出结果 System.out.println("您本次消费: " + price); System.out.println("\n 请输入您的付款面额:"+price); i