租车系统的Java简单实现

一开始觉得很简单，听老师讲很有思路。想好了然后开始写，就出现问题了，还是太年轻。看了慕友的代码，然后在自己写，收获还是有的，比如让我重新认识了 instanceof

car.java

package com.car_rental;

public class Car {
    public String name;//车名
    public float rent;//租金

}

Bus.java

package com.car_rental;

public class Bus extends Car {
    private int carry;//载客量
    public Bus(String name,int carry,float rent){
        this.name=name;
        this.carry=carry;
        this.rent=rent;
    }
    public float getCarry() {
        return carry;
    }
    @Override
    public String toString() {

        return name+"\t"+ rent + "元/天\t"+carry+"人\t";
    }
}

Truck.java

package com.car_rental;

public class Truck extends Car {
    private float load; //载重量
    public Truck(String name,float load,float rent){
        this.name=name;
        this.load=load;
        this.rent=rent;
    }
    public float getLoad() {
        return load;
    }
    @Override
    public String toString() {
        return name+"\t"+rent+"元/天\t"+load+"吨\t";
    }

}

Pika.java

package com.car_rental;

public class Pika extends Car {
    private float load; //载重量
    private int carry; //载客量

    public Pika(String name,float load,int carry,float rent){
        this.name=name;
        this.load=load;
        this.carry=carry;
        this.rent=rent;
    }

    public float getLoad() {
        return load;
    }

    public float getCarry() {
        return carry;
    }
    @Override
    public String toString() {
        return name+"\t"+rent+"元/天\t"+load+"吨        "+carry+"人\t";
    }

}

Rent_car.java

package com.car_rental;
import java.util.Scanner;

public class Rent_car {
    Scanner input=new Scanner(System.in);
    //车库  定义父类的对象数组来 根据子类的特性 存入
    public Car[] car={new Truck("小货车",3.5f,500f),new Truck("大货车",7.8f,800f),new Bus("小客车",12,400f),
            new Bus("大客车",25,900f),new Pika("小皮卡",1.1f,4,600f),new Pika("大皮卡",2.5f,6,1100f)};
    //总界面+操作
    public void welcome(){
        System.out.println("欢迎使用租车系统");
        while(true){
            System.out.println("请问您是否租车");
            System.out.println("是：输入1   否：输入任意键退出");
            int n;
            if((n=input.nextInt())==1){
                System.out.println("您可租车的类型及其价目表:");
                //车辆信息
                getcarList();
                System.out.println("请输入您要租汽车的数量");
                int car_num;//租车数量
                car_num=input.nextInt();
                //待租的汽车  将车库的信息放入其中
                Car[] car_renting=new Car[car_num];
                for(int i=1;i<=car_num;i++){
                    int num;
                    System.out.println("请输入您要租的第"+i+"辆车的序号:");
                    num=input.nextInt();
                    car_renting[i-1]=car[num-1];
                }
                //租车天数
                int rent_day;
                System.out.println("请输入租车天数");
                rent_day=input.nextInt();
                System.out.println("您的账单");
                //总载人量
                gettotalCarry(car_renting);
                //总载重量
                gettotalLoad(car_renting);
                //总金额
                getTotalPay(car_renting,rent_day);
            }
            else{
                System.out.println("输入错误 已退出");
                break;
            }

        }
    }
    //输出车库的全部信息
    public void getcarList(){
        int i;
        System.out.println("序号\t汽车名称\t租金\t\t容量 ");
        for(i=0;i<car.length;i++){
            //车库中各信息不同  根据关键词 instanceof 来判别 在 向下转换输出
            if(car[i] instanceof Bus){
                System.out.println((i+1)+"\t"+((Bus)car[i]));
            }
            else if(car[i] instanceof Truck){
                System.out.println((i+1)+"\t"+((Truck)car[i]));
            }
            else{//car[i] instanceof Pika
                System.out.println((i+1)+"\t"+((Pika)car[i]));
            }
        }
    }
    //总载人量
    public void gettotalCarry(Car[] car_renting){
        int totalCarry=0;
        System.out.println("**可载人的车：");
        for(int i=0;i<car_renting.length;i++){
            //载人有 Bus 和 Pika 
            if(car_renting[i] instanceof Bus){
                totalCarry+=((Bus)car_renting[i]).getCarry();
                System.out.print(((Bus)car_renting[i]).name+"  ");
            }
            else if(car_renting[i] instanceof Pika){
                totalCarry+=((Pika)car_renting[i]).getCarry();
                System.out.print(((Pika)car_renting[i]).name+"  ");
            }
        }
        System.out.println("共载人数："+totalCarry+"人");
    }
    //总载重量
    public void gettotalLoad(Car[] car_renting){
        float totalLoad=0f;
        System.out.println("**载货的车有:");
        for(int i=0;i<car_renting.length;i++){
            //载重量有Truck 和 Pika
            if(car_renting[i] instanceof Truck){
                totalLoad+=((Truck)car_renting[i]).getLoad();
                System.out.print(((Truck)car_renting[i]).name+"  ");
            }
            else if(car_renting[i] instanceof Pika){
                totalLoad+=((Pika)car_renting[i]).getLoad();
                System.out.print(((Pika)car_renting[i]).name+"  ");
            }
        }
        System.out.println("共载重："+totalLoad+"吨");
    }
    //总花费
    public void getTotalPay(Car[] car_renting,int rent_day){
        float totalPay=0f;
        for(int i=0;i<car_renting.length;i++){
            totalPay+=car_renting[i].rent;
        }
        totalPay *= rent_day;
        System.out.println("**租车总价格:"+totalPay);
    }

}

test.java

package com.car_rental;

public class test {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Rent_car rent=new Rent_car();
        rent.welcome();
    }
}