汽车租赁问题--涉及知识点（面向对象，继承，多态）：instanceof，向下类型转换，父类引用指向子类对象

题目内容

实现租车的挑选，租金的计算等功能

Vehicle.java

package cn.kgc.tangcco;
/**
 * 
 * @author 10570
 *2019-12-31
 */
public abstract class Vehicle {
	private String vehicleID; //车牌号
	private String vehicleBrand; //品牌
	private int perRent;//日租金
	public abstract double calcRent(int days);//租车需要的租金（便于重写的一个抽象方法）
	//创建vehicle的无参构造函数，一般情况下无参构造都要写明
	public Vehicle() {}
	//创建get。set方法
	public String getVehicleID() {
		return vehicleID;
	}
	public void setVehicleID(String vehicleID) {
		this.vehicleID = vehicleID;
	}
	public String getVehicleBrand() {
		return vehicleBrand;
	}
	public void setVehicleBrand(String vehicleBrand) {
		this.vehicleBrand = vehicleBrand;
	}
	public int getPerRent() {
		return perRent;
	}
	public void setPerRent(int perRent) {
		this.perRent = perRent;
	}
	//代参构造函数
	public Vehicle(String vehicleID, String vehicleBrand, int perRent) {
		this.vehicleID = vehicleID;
		this.vehicleBrand = vehicleBrand;
		this.perRent = perRent;
	}
}

Bus.java

package cn.kgc.tangcco;

public class Bus extends Vehicle {
	int seatCount ; //座位

	public int getSeatCount() {
		return seatCount;
	}
	public void setSeatCount(int seatCount) {
		this.seatCount = seatCount;
	}
	public Bus(String vehicleID ,String vehicleBrand, int perRent, int seatCount) {
		super(vehicleID, vehicleBrand, perRent);
		this.seatCount = seatCount;
	}
	//租金方式，重写方法
	public double calcRent(int days) {
		double price = this.getPerRent()*days;
		if(days > 3 && days <=7) {
			price *= 0.9;
		}else if(days > 7 && days <=7) {
			price *= 0.8;
			
		}else if(days > 30 && days <=150) {
			price *= 0.7;
		}else if(days > 150){
			price *= 0.6;
		}
		return price;
	}
}

Car.java

package cn.kgc.tangcco;

public  class Car extends Vehicle{
	private String types; //车的类型
 
	public String getTypes() {
		return types;
	}

	public void setTypes(String types) {
		this.types = types;
	}
	
	public Car(String vehicleID,String vehicleBrand ,int perRent, String types) {
		super(vehicleID, vehicleBrand, perRent);
		this.types = types;
	}
	//租金方式，重写方法
	public  double calcRent(int days) {
		int price = this.getPerRent()*days;
		if(days >= 7 && days < 30) {
			price *= 0.9;
		}else if(days > 30 && days <=150) {
			price *= 0.8;
		}else if(days > 150) {
			price *= 0.7;
		}
		return price;
	}
}

ManageOperation,java

package cn.kgc.tangcco;
public class ManageOperation {
	public Vehicle[] magOper = new Vehicle[8];
	//车辆的初始化
	public void init() {
		magOper[0]= new Car("京NY","宝马",800,"X6"); //Vehicle m = new Car();父类引用指向子类对象
		magOper[1]= new Car("京BP","宝马",600,"550i");
		magOper[2]= new Car("京TY","别克",300,"林荫大道");
		magOper[3]= new Car("京ER","别克",600,"GL8");
		magOper[4]= new Bus("京WE","金龙",800,16);
		magOper[5]= new Bus("京UI","金杯",800,16);
		magOper[6]= new Bus("京PJ","金龙",1600,34);
		magOper[7]= new Bus("京GD","金杯",1600,34);
	}
	//租赁汽车
	public Vehicle vehicleLeastOut(String vehicleBrand, String types, int seatCount) {
		Vehicle moto = null;  //一个临时存储的地址
		for(Vehicle mymoto : magOper) {  
			//instanceof   查看所查找的内容中是否包含 某个值
			if(mymoto instanceof Car) {   //遍历出的对象是什么类型  Car Or Bus
				Car car= (Car)mymoto;    //向下转型必须强转
				if(car.getVehicleBrand().equals(vehicleBrand)&&car.getTypes().equals(types)) {
					moto = car;
					break;
				}
			}else {
				Bus bus = (Bus)mymoto;
				if(bus.getVehicleBrand().equals(vehicleBrand) && bus.getSeatCount()==seatCount) {
					moto = bus;
					break;
				}
			}
		}
		return moto;
	}
}

RentManage.java

package cn.kgc.tangcco;
import java.util.Scanner;
public class RentManage {
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		//汽车业务类需要调用，才有车
		ManageOperation mango = new ManageOperation();  
		//汽车的初始化，即先确定一下有的车
		mango.init();   
		Vehicle moto = null;
//		Random r = new Random();
//		int ran = r.nextInt();
		System.out.println("---------欢迎来到汽车城----------");
		System.out.println("你的租车类型：1、轿车\t2、客车");
		System.out.print("你的选择：");
		int choose = input.nextInt();
		//租车的三个条件
		String vehicleBrand = "";//品牌
		String types = "";//车的类型，属于轿车
		int seatCount = 0;//座位数 ，属于客车
		if(choose == 1) {
			
			//租轿车
			System.out.println("请选择你要的品牌：1、宝马\t2、别克");
			System.out.print("你的选择：");
			choose = input.nextInt();
			if(choose == 1) {
				vehicleBrand = "宝马";
				System.out.println("请选择你要的型号：1、X6\t 2、550i");
				System.out.print("你的选择：");
				choose = input.nextInt();
				types = (choose == 1)?"X6":"550i";
			}else {
				vehicleBrand = "别克";
				System.out.println("请你选择你要的型号：1、林荫大道\t2、GL8");
				System.out.print("你的选择：");
				choose = input.nextInt();
				types = (choose == 1)?"林荫大道":"GL8";
			}
		}else {
			//租客车
			System.out.println("请选择你要的品牌：1、金龙\t2、金杯");
			System.out.print("你的选择：");
			choose = input.nextInt();
			if(choose == 1 ) {
				vehicleBrand = "金龙";
				System.out.println("你要的座位数：1、16座\t 2、34座");
				choose = input.nextInt();
				seatCount = (choose == 1)?16:34;
			}else {
				vehicleBrand = "金杯";
				System.out.println("你要的座位数：1、16座\t 2、34座");
				choose = input.nextInt();
				seatCount = (choose == 1)?16:34;
			}
		}
	moto = mango.vehicleLeastOut(vehicleBrand, types, seatCount);
	System.out.println("请输入要租的天数：");
	int days = input.nextInt();
	double money = moto.calcRent(days);
	System.out.println(vehicleBrand+types+seatCount);
	System.out.println("你租的车牌："+moto.getVehicleID());
	System.out.println("你的租金是："+money+"元");
	}
}

这是之前的一道小的作业题，自己做完之后，对功能进行了实现。之后又参考了老师给打案例，进行了完善以及注释上的批注。今天发一下，借于大家参考。欢迎提出问题。
谢谢