1、设计四个类,分别是:(知识点:抽象类及抽象方法)
(1)Shape表示图形类,有面积属性area、周长属性per,颜色属性color,有两个构造方法(一个是默认的、一个是为颜色赋值的),还有3个抽象方法,
分别是:getArea计算面积、getPer计算周长、showAll输出所有信息,还有一个求颜色的方法getColor。
(2)2个子类:
1)Rectangle表示矩形类,增加两个属性,Width表示长度、height表示宽度,重写getPer、getArea和showAll三个方法,另外又增加一个构造方法,
(一个是默认的、一个是为高度、宽度、颜色赋值的)。
2)Circle表示圆类,增加1个属性,radius表示半径,重写getPer、getArea和showAll三个方法,另外又增加两个构造方法(为半径、颜色赋值的)。
(3)一个测试类PolyDemo,在main方法中,声明创建每个子类的对象,并调用2个子类的showAll方法。
package com.gyq.chapterOne;
public abstract class Shape1 {
protected double area;
protected double per;
protected String color;
public Shape1() {
}
public Shape1(String color) {
super();
this.color = color;
}
public String getColor() {
return color;
}
public void setColor(String color) {
this.color = color;
}
public abstract void getArea();
public abstract void getPer();
public abstract void showAll();
}
package com.gyq.chapterOne;
import java.awt.Color;
public class Rectangle1 extends Shape1{
private int width;
private int height;
public Rectangle1() {
}
public Rectangle1(int width, int height,String color) {
super(color);
this.width = width;
this.height = height;
}
@Override
public void getArea() {
area = width * height;
}
@Override
public void getPer() {
per = (width + height) * 2;
}
@Override
public void showAll() {
System.out.println("矩形面积为:"+area+",举行周长为:"+per+",矩形颜色为:"+color);
}
}
package com.gyq.chapterOne;
public class Circle1 extends Shape1{
private int radius;
public Circle1() {
super();
// TODO Auto-generated constructor stub
}
public Circle1(int radius,String color) {
super(color);
this.radius = radius;
}
@Override
public void getArea() {
area = radius * radius * 3.14;
}
@Override
public void getPer() {
per = 2 * radius * 3.14;
}
@Override
public void showAll() {
System.out.println("圆的面积为:"+area+",周长为:"+per+",颜色为:"+color);
}
}
package com.gyq.chapterOne;
public class PolyDeom {
public static void main(String[] args) {
// TODO Auto-generated method stub
Rectangle1 r = new Rectangle1(3, 4, "蓝");
Circle1 c = new Circle1(2, "黄");
r.getArea();
r.getPer();
r.showAll();
c.getArea();
c.getPer();
c.showAll();
}
}
2、Cola公司的雇员分为以下若干类:(知识点:多态)
(1) ColaEmployee :这是所有员工总的父类,属性:员工的姓名,员工的生日月份。
Ÿ 方法:getSalary(int month) 根据参数月份来确定工资,如果该月员工过生日,则公司会额外奖励100 元。
(2) SalariedEmployee : ColaEmployee 的子类,拿固定工资的员工。
Ÿ 属性:月薪
(3) HourlyEmployee :ColaEmployee 的子类,按小时拿工资的员工,每月工作超出160 小时的部分按照1.5 倍工资发放。
Ÿ 属性:每小时的工资、每月工作的小时数
(4) SalesEmployee :ColaEmployee 的子类,销售人员,工资由月销售额和提成率决定。
Ÿ 属性:月销售额、提成率
(5) 定义一个类Company,在该类中写一个方法,调用该方法可以打印出某月某个员工的工资数额,写一个测试类TestCompany,在main方法,把若干各种类型的员工放在一个
ColaEmployee 数组里,并单元出数组中每个员工当月的工资。
package com.gyq.chapterOne;
public class ColaEmployee {
protected String name;
protected int birthday;
public ColaEmployee() {
}
public ColaEmployee(String name, int birthday) {
super();
this.name = name;
this.birthday = birthday;
}
public double getSalary(int month) {
return 0;
}
}
package com.gyq.chapterOne;
public class SalariedEmployee extends ColaEmployee{
double Salary;
public SalariedEmployee() {
super();
// TODO Auto-generated constructor stub
}
public SalariedEmployee(double salary,String name, int birthday) {
super(name, birthday);
this.Salary = salary;
}
public double getSalary(int month) {
if (super.birthday==birthday) {
return Salary + 100;
} else {
return Salary;
}
}
}
package com.gyq.chapterOne;
public class HourlyEmployee extends ColaEmployee{
int hourSalary;
int hour;
public HourlyEmployee() {
super();
// TODO Auto-generated constructor stub
}
public HourlyEmployee(int hourSalary, int hour,String name, int birthday) {
super(name, birthday);
this.hourSalary = hourSalary;
this.hour = hour;
}
public double getSalary(int month) {
if (super.birthday==birthday) {
if (hour>160) {
return hourSalary * 160 + hourSalary * (hour - 160) * 1.5 +100;
} else {
return hourSalary*hour+100;
}
} else {
if (hour>160) {
return hourSalary * 160 + hourSalary * (hour - 160) * 1.5;
} else {
return hourSalary*hour;
}
}
}
}
package com.gyq.chapterOne;
public class SalesEmployee extends ColaEmployee{
int monthSales;
double add;
public SalesEmployee() {
super();
// TODO Auto-generated constructor stub
}
public SalesEmployee(int monthSales, double add,String name, int birthday) {
super(name, birthday);
this.monthSales = monthSales;
this.add = add;
}
public double getSalary(int mon) {
if (super.birthday==birthday) {
return monthSales*add+100;
} else {
return monthSales*add;
}
}
}
package com.gyq.chapterOne;
import java.time.Month;
public class Company {
public void getSalary(ColaEmployee a,int month) {
System.out.println(a.name + "在" + month + "月的月薪为" + a.getSalary(month) + "元");
}
}
package com.gyq.chapterOne;
public class TestCompany {
public static void main(String[] args) {
// TODO Auto-generated method stub
ColaEmployee[] a= {new SalariedEmployee(10000,"James",4),new HourlyEmployee(60, 200, "Licy", 10),new SalesEmployee(9000, 1.8, "Coco", 2)};
for (int i = 0; i < a.length; i++) {
new Company().getSalary(a[i], 4);
}
}
}
3、利用接口实现动态的创建对象:(知识点:接口 )
(1)创建4个类
1.苹果
2.香蕉
3.葡萄
4.园丁
(2)在三种水果的构造方法中打印一句话.
以苹果类为例
class apple
{
public apple()
{
System.out.println(“创建了一个苹果类的对象”);
}
}
(3)类图如下:
(4)要求从控制台输入一个字符串,根据字符串的值来判断创建三种水果中哪个类的对象。
package com.gyq.chapterOne;
public interface Fruit {
}
package com.gyq.chapterOne;
public class Apple implements Fruit{
public Apple() {
System.out.println("创建了一个苹果对象");
}
}
package com.gyq.chapterOne;
public class Banana implements Fruit{
public Banana() {
System.out.println("创建了一个香蕉对象");
}
}
package com.gyq.chapterOne;
public class Grape implements Fruit{
public Grape() {
System.out.println("创建了一个葡萄对象");
}
}
package com.gyq.chapterOne;
import java.util.Scanner;
public class Gardener {
public Fruit create() {
System.out.println("请输入你想要创建的水果对象");
Scanner input = new Scanner(System.in);
String name = input.next();
Fruit fruit = null;
switch (name) {
case "苹果":
fruit = new Apple();
break;
case "香蕉":
fruit = new Banana();
break;
case "葡萄":
fruit = new Grape();
break;
}
input.close();
return fruit;
}
}
package com.gyq.chapterOne;
public class FruitDeom {
public static void main(String[] args) {
// TODO Auto-generated method stub
Gardener g = new Gardener();
g.create();
}
}