定義不同的汽車類

主類：

package?com.imooc;

public?class?Car?{
		private?int?carNumber;?//汽車的序號
		private?String?carName;?//汽車的名字
		private?int?carRent;//租車的費用
		
		public?int?getCarNumber()?{
			return?carNumber;
		}
		public?void?setCarNumber(int?carNumber)?{
			this.carNumber?=?carNumber;
		}
		public?String?getCarName()?{
			return?carName;
		}
		public?void?setCarName(String?carName)?{
			this.carName?=?carName;
		}
		public?int?getCarRent()?{
			return?carRent;
		}
		public?void?setCarRent(int?carRent)?{
			this.carRent?=?carRent;
		}
		
}

三個不同的汽車類

package?com.imooc;

public?class?PassengerCar?extends?Car??{
	
	private?int?passengers;//載客量
	
	public?PassengerCar(int?carNumber,String?carName,int?carRent,int?passengers){?//定義有參函數(shù)
		?this.setCarName(carName);
		?this.setCarNumber(carNumber);
		?this.setPassengers(passengers);
		?this.setCarRent(carRent);
	}

	public?int?getPassengers()?{
		return?passengers;
	}

	public?void?setPassengers(int?passengers)?{
		this.passengers?=?passengers;
	}
	

}

package?com.imooc;

public?class?Truck?extends?Car?{
	
	private?int?cargo;//載貨量
	
	public?Truck(int?carNumber,String?carName,int?carRent,int?cargo){?//定義一個有參的構(gòu)造方法?
		this.setCarName(carName);
		this.setCarNumber(carNumber);
		this.setCarRent(carRent);
		this.setCargo(cargo);
	}
	
	public?int?getCargo()?{
		return?cargo;
	}

	public?void?setCargo(int?cargo)?{
		this.cargo?=?cargo;
	}

}

package?com.imooc;

public?class?PickUp?extends?Car?{
	private?int?cargo;//載貨量
	private?int?passengers;//載客量
	
	public?PickUp(int?carNumber,String?carName,int?carRent,int?cargo,int?passengers){
		this.setCargo(cargo);
		this.setCarName(carName);
		this.setCarNumber(carNumber);
		this.setCarRent(carRent);
		this.setPassengers(passengers);
	}
	
	public?int?getCargo()?{
		return?cargo;
	}
	public?void?setCargo(int?cargo)?{
		this.cargo?=?cargo;
	}
	public?int?getPassengers()?{
		return?passengers;
	}
	public?void?setPassengers(int?passengers)?{
		this.passengers?=?passengers;
	}
	
	
}

最后是主代碼

package?com.imooc;

import?java.util.ArrayList;
import?java.util.Arrays;
import?java.util.List;
import?java.util.Scanner;

public?class?CarSystem?{

	/**
	?*?@param?args
	?*/
	public?static?void?main(String[]?args)?{
		System.out.println("歡迎使用答答汽車系統(tǒng)：");
		System.out.println("你是否要租車：1是?0否");
		Scanner?sc?=?new?Scanner(System.in);?
		int?input?=?sc.nextInt();????????????//?new?Sacnner(System.in).nextInt()?才是有效的數(shù)
		if(input?==?1){
			System.out.println("您可以租車的類型及價目表如下:?");
			System.out.println("序號\t"+"汽車名稱\t"+"租金\t"+"容量\t");
			Car?car1?=?new?PassengerCar(1,?"奧迪A4",?500,?4);
			Car?car2?=?new?PassengerCar(2,?"馬自達6",?400,?4);
			Car?car3?=?new?PickUp(3,?"皮卡雪6",?450,?2,?4);
			Car?car4?=?new?Truck(4,?"金龍",?800,?20);
			Car?car5?=?new?Truck(5,?"松花江",?400,?4);
			Car?car6?=?new?Truck(6,?"超大車",?1000,?20);
			Car[]?rentcars?=?{car1,car2,car3,car4,car5,car6};
			for?(Car?rentcar?:?rentcars){//列出所有的車
				if?(rentcar?instanceof?PassengerCar){
					System.out.println(rentcar.getCarNumber()+".\t"+rentcar.getCarName()+"\t"+rentcar.getCarRent()+"元/天\t載人:"+((PassengerCar)rentcar).getPassengers());
				}else?if(rentcar?instanceof?PickUp){
					System.out.println(rentcar.getCarNumber()+".\t"+rentcar.getCarName()+"\t"+rentcar.getCarRent()+"元/天\t載人:"+((PickUp)rentcar).getPassengers()+"\t載貨:"+((PickUp)rentcar).getCargo()+"噸");
				}else?if(rentcar?instanceof?Truck){
					System.out.println(rentcar.getCarNumber()+".\t"+rentcar.getCarName()+"\t"+rentcar.getCarRent()+"元/天\t載貨:"+((Truck)rentcar).getCargo()+"噸");
				}
			}
			System.out.println("請你輸入要租車的數(shù)量");
			int?counts?=?sc.nextInt();
			List<Car>?bookcars?=?new?ArrayList<>();//定義一個list去存儲要租的車
			if?(counts>0){
				for(int?count?=?1;?count<=counts;?count?++){
					System.out.println("請你輸入第"+count+"輛車的序號");
					int?selectcar?=?sc.nextInt();
					bookcars.add(rentcars[selectcar-1]);//保存客戶輸入的車的序號
				}
				System.out.println("請輸入要租的天數(shù)");
				int?rentdays?=?sc.nextInt();
				System.out.println("您的賬單為：");
				int?totalFee?=?0;
				int?totalCargo?=?0;
				int?totalPassenger?=?0;
				String?allcarname?=?"";
				for(int?i=0;?i<bookcars.size()?;i++){//列出所有用戶所選的汽車
					if(allcarname?!=?""){
						allcarname?=?allcarname.concat(",");
					}
					Car?rentcar1?=?bookcars.get(i);
					totalFee?=?totalFee?+?rentcar1.getCarRent()*rentdays;
					if?(rentcar1?instanceof?PassengerCar){
						totalPassenger?=?totalPassenger?+?((PassengerCar)rentcar1).getPassengers();
					}
					if?(rentcar1?instanceof?PickUp){
						totalPassenger?=?totalPassenger?+?((PickUp)rentcar1).getPassengers();
						totalCargo?=?totalCargo?+??((PickUp)rentcar1).getCargo();
					}
					if?(rentcar1?instanceof?Truck){
						totalCargo?=?totalCargo?+??((Truck)rentcar1).getCargo();
					}
					allcarname?=?allcarname.concat(rentcar1.getCarName());
				}
				System.out.println("租的車有："+allcarname);
				System.out.println("總金額:?"+totalFee);
				System.out.println("總載貨量:?"+totalCargo);
				System.out.println("總載客量:?"+totalPassenger);

			}else
			System.out.println("請輸入正確的數(shù)量");
		}else{
			System.out.println("謝謝使用!");
		}
	}

}