正文
day11作业
小程序：扫一扫查出行【扫一扫了解最新限行尾号】
复制小程序
一.选择题
1.B 2.D 3.AB 4.C
二.判断题
1.× 2.√
三.简答题
1.
多态就是事物存在的多种形态。
提高程序的复用性，提高程序的可扩展性和可维护性。
2.
向上转型是指父类引用指向子类对象，向下转型是指子类引用指向父类对象。
import java.util.Scanner;
class Test5_Pizza {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("请选择想要制作的披萨(1.培根披萨 2.海鲜披萨)：");
int choice = sc.nextInt();
System.out.println("请输入培根克数：");
int gram = sc.nextInt();
System.out.println("请输入披萨大小：");
int size = sc.nextInt();
System.out.println("请输入披萨价格：");
int price = sc.nextInt();
if (choice == 1) {
PeiGenPizza p1 = new PeiGenPizza(gram,size,price);
p1.show1();
}else if(choice == 2){
HaiXianPizza p2 = new HaiXianPizza(gram,size,price);
p2.show2();
}
}
}
class Pizza {
private int gram;
private int size;
private int price;
public Pizza(){}
public Pizza(int gram,int size,int price){
this.gram = gram;
this.size = size;
this.price = price;
}
public void setGram(int gram){
this.gram = gram;
}
public int getGram(){
return gram;
}
public void setSize(int size){
this.size = size;
}
public int getSize(){
return size;
}
public void setPrice(int price){
this.price = price;
}
public int getPrice(){
return price;
}
}
class PeiGenPizza extends Pizza {
public PeiGenPizza(){}
public PeiGenPizza(int gram,int size,int price){
super(gram,size,price);
}
public void show1(){
System.out.println("名称：培根披萨" + "\n" + "价格：" + getPrice() + "元" + "\n" + "大小：" + getSize() + "寸" + "\n" + "培根克数：" + getGram() + "克");
}
}
class HaiXianPizza extends Pizza {
public HaiXianPizza(){}
public HaiXianPizza(int gram,int size,int price){
super(gram,size,price);
}
public void show2(){
System.out.println("名称：海鲜披萨" + "\n" + "价格：" + getPrice() + "元" + "\n" + "大小：" + getSize() + "寸" + "\n" + "培根克数：" + getGram() + "克");
}
}
import java.util.Scanner;
class Test6_Drink {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("请选择饮料(1.咖啡 2.矿泉水 3.可乐)：");
int choice = sc.nextInt();
System.out.println("请输入购买容量：");
int capacity = sc.nextInt();
System.out.println("您购买饮料信息如下。");
if (choice == 1) {
System.out.println("请问是否需要配料(1.加糖 2.加奶 3.什么都不加):");
int add = sc.nextInt();
Coffee c1 = new Coffee();
c1.setCapacity(capacity);
switch (add) {
case 1:
c1.setAdd("加糖");
break;
case 2:
c1.setAdd("加奶");
break;
case 3:
c1.setAdd("什么都不加");
break;
}
c1.show1();
}else if(choice == 2){
SpringWater s = new SpringWater(capacity);
s.show2();
}else if (choice == 3) {
System.out.println("请选择(1.可口可乐 2.百事可乐):");
int brand = sc.nextInt();
Cola c2 = new Cola();
c2.setCapacity(capacity);
switch (brand) {
case 1:
c2.setBrand("可口可乐");
break;
case 2:
c2.setBrand("百事可乐");
break;
}
c2.show3();
}
}
}
class Drink {
private int capacity;
public Drink(){}
public Drink(int capacity){
this.capacity = capacity;
}
public void setCapacity(int capacity){
this.capacity = capacity;
}
public int getCapacity(){
return capacity;
}
}
class Coffee extends Drink {
private String add;
public Coffee(){}
public Coffee(int capacity,String add){
super(capacity);
this.add = add;
}
public void setAdd(String add){
this.add = add;
}
public String getAdd(){
return add;
}
public void show1(){
System.out.println("名称：咖啡" + "\n" + "添加配料：" + getAdd() + "\n" + "容量：" + getCapacity());
}
}
class SpringWater extends Drink {
public SpringWater(){}
public SpringWater(int capacity){
super(capacity);
}
public void show2(){
System.out.println("名称：矿泉水" + "\n" + "容量：" + getCapacity());
}
}
class Cola extends Drink {
private String brand;
public Cola(){}
public Cola(int capacity,String brand){
super(capacity);
this.brand = brand;
}
public void setBrand(String brand){
this.brand = brand;
}
public String getBrand(){
return brand;
}
public void show3(){
System.out.println("名称：" + getBrand() + "\n" + "容量：" + getCapacity());
}
}
