主类

import java.util.Scanner;
public class carRentSystem{
    static carRentSystem mySystem = new carRentSystem();
    A4 myA4 = new A4();
    Maz myMaz = new Maz();
    Pic myPic = new Pic();
    Jin myJin = new Jin();
    Son mySon = new Son();
    Yiw myYiw = new Yiw();
    public static void main(String[] args){
        mySystem.YorN();
    }
    public void YorN(){
        System.out.println("欢迎光临，请问您想要租车吗？\n1.是\n2.否");
        Scanner myscanner = new Scanner(System.in);
        int choice = myscanner.nextInt();
        if(choice == 1){
            choosecar();
        }else{
            System.out.println("非常抱歉没能帮到您，欢迎下次光临");
        }
    }
    public void choosecar(){
        System.out.println("您可租车的类型及其价目表：");
        System.out.println("序号  汽车名称  租金      容量");
        System.out.println("1.    奥迪A4    500元/天  载人：4人");
        System.out.println("2.    马自达6   400元/天  载人：4人");
        System.out.println("3.    皮卡雪6   450元/天  载人：4人 载货：2吨");
        System.out.println("4.    金龙      800元/天  载人：20人");
        System.out.println("5.    松花江    400元/天  载货：4吨");
        System.out.println("6.    依维柯    1000元/天 载货：20吨");
        System.out.print("请输入您要租车的数量：");
        Scanner myscanner = new Scanner(System.in);
        int times = myscanner.nextInt();
        int price = 0;
        for(int i = 1;i <=times;i++){
            System.out.println("请输入您要租的汽车的序号：");
            int carNum = myscanner.nextInt();
            switch(carNum){
                case 1:
                    price = price + myA4.getPrice();
                case 2:
                    price = price + myMaz.getPrice();
                case 3:
                    price = price + myPic.getPrice();
                case 4:
                    price = price + myJin.getPrice();
                case 5:
                    price = price + mySon.getPrice();
                case 6:
                    price = price + myYiw.getPrice();
            }
        }
        System.out.println("选车完毕，这是您的账单：");
        System.out.println("总价："+price+"元");
    }
}

车类格式

public class A4{
    String name = "奥迪A4";
    int price = 500;
    public int getPrice(){
        return price;
    }
}