练习一：答答租车系统

package com.jiay.dadacar;

public class Car {
    public String name;//车名
    public int rental;//租金

    public String getName() {
        return name;
    }
    public int getRental() {
        return rental;
    }
}

package com.jiay.dadacar;

public class PassengerCar extends Car {
    public int zaiRen;

    public PassengerCar(String name, int rental, int zaiRen) {
        this.name = name;
        this.rental = rental;
        this.zaiRen = zaiRen;   
    }

    public int getZaiRen() {
        return zaiRen;
    }
}

package com.jiay.dadacar;

public class ThingCar extends Car {
    public int zaiHuo;

    public ThingCar(String name, int rental, int zaiHuo) {
        this.name = name;
        this.rental = rental;
        this.zaiHuo = zaiHuo;
    }

    public int getZaiHuo() {
        return zaiHuo;
    }
}

package com.jiay.dadacar;

public class PikCar extends Car {
    public int zaiRen;
    public int zaiHuo;

    public PikCar(String name, int rental, int zaiRen, int zaiHuo) {
        this.name = name;
        this.rental = rental;
        this.zaiRen = zaiRen;
        this.zaiHuo = zaiHuo;
    }

    public int getZaiRen() {
        return zaiRen;
    }

    public int getZaiHuo() {
        return zaiHuo;
    }
}

package com.jiay.dadacar;

import java.util.Scanner;

public class CarSystem {

    //可供租的车的信息
    public static Car[] carsForRent = { new PassengerCar("奥迪A4", 500, 4), new PassengerCar("马自达6", 400, 4),
            new PikCar("皮卡雪6", 450, 4, 2), new PassengerCar("金龙", 800, 20), new ThingCar("松花江", 400, 4),
            new ThingCar("依维柯", 1000, 20) };

    //用于接收控制台输入
    static Scanner scanner = new Scanner(System.in);

    static StringBuffer psb=new StringBuffer(" ");//记录载人车名称
    static StringBuffer tsb=new StringBuffer(" ");//记录载货车名称
    static int allRen=0;//记录总人数
    static int allHuo=0;//记录总吨数
    static int allRental=0;//记录总租金

    //判断是否需要租车
    public static boolean isRent() {
        String isRent = scanner.next();
        if (isRent.equals("1")) {
            return true;
        }else {
            return false;
        }
    }

    //显示出租的车的具体信息
    public static void displayCars() {
        System.out.println("您可租车的类型及其价目表：");
        System.out.println("序号\t汽车名称\t\t租金\t\t容量");
        //下面输出车辆信息
        int i=1;
        for (Car car : carsForRent) {
            if (car instanceof PassengerCar) {
                System.out.println(""+i+"\t"+car.getName()+"\t\t"
                                   +car.getRental()+"元/天\t\t"+"载人:"+((PassengerCar)car).getZaiRen()+"人");
            }

            if (car instanceof ThingCar) {
                System.out.println(""+i+"\t"+car.getName()+"\t\t"
                                   +car.getRental()+"元/天\t\t"+"载货:"+((ThingCar)car).getZaiHuo()+"吨");
            }

            if (car instanceof PikCar) {
                System.out.println(""+i+"\t"+car.getName()+"\t\t"
                                   +car.getRental()+"元/天\t\t"+"载人:"+((PikCar)car).getZaiRen()+"人"+" 载货:"+((PikCar)car).getZaiHuo()+"吨");
            }

            i++;
        }
    }

    public static void main(String[] args) {
        System.out.println("欢迎使用答答租车系统！");
        System.out.println("您是否要租车：1是   0否");
        if (isRent()) {
            displayCars();

            System.out.println("请输入您要租汽车的数量：");
            int rentNum = scanner.nextInt();
            Car currentCar;//记录当前租用的汽车

            for (int i = 0; i < rentNum; i++) {
                System.out.println("请输入第"+(i+1)+"辆车的序号：");
                currentCar =carsForRent[scanner.nextInt()-1];
                allRental+=currentCar.getRental();
                if (currentCar instanceof PassengerCar ) {
                    psb.append(currentCar.getName()).append("  ");
                    allRen+=((PassengerCar)currentCar).getZaiRen();
                }
                if (currentCar instanceof ThingCar) {
                    tsb.append(currentCar.getName()).append("  ");
                    allHuo+=((ThingCar)currentCar).getZaiHuo();
                }
                if (currentCar instanceof PikCar) {
                    psb.append(currentCar.getName()).append("  ");
                    tsb.append(currentCar.getName()).append("  ");
                    allRen+=((PikCar)currentCar).getZaiRen();
                    allHuo+=((PikCar)currentCar).getZaiHuo();
                }
            }

            System.out.println("请输入租车天数：");
            int rentDays = scanner.nextInt();
            allRental*=rentDays;
            scanner.close();
            System.out.println("您的账单：");
            if (allRen!=0) {
                System.out.println("***可载人的车有：");
                System.out.println(psb+"共载人："+allRen+"人");
            }else {
                System.out.println("您没有租用载人的车");
            }
            if (allHuo!=0) {
                System.out.println("***可载货的车有：");
                System.out.println(tsb+"共载货："+allHuo+"吨");
            }else {
                System.out.println("您没有租用载货的车");
            }
            System.out.println("***租车总价格："+allRental);

        }else {
            System.out.println("Bye");
        }
    }
}