JAVA-2.0-上機

1、設計四個類,分別是:(知識點:抽象類及抽象方法)(1)Shape表示圖形類,有面積屬性area、周長屬性per,顏色屬性color,有兩個構造方法(一個是默認的、一個是為顏色賦值的),還有3個抽象方法,分別是:getArea計算面積、getPer計算周長、showAll輸出所有信息,還有一個求顏色的方法getColor。(2)2個子類:    1)Rectangle表示矩形類,增加兩個屬性,Width表示長度、height表示寬度,重寫getPer、getArea和showAll三個方法,另外又增加一個構造方法(一個是默認的、一個是為高度、寬度、顏色賦值的)。    2)Circle表示圓類,增加1個屬性,radius表示半徑,重寫getPer、getArea和showAll三個方法,另外又增加兩個構造方法(為半徑、顏色賦值的)。 (3)一個測試類PolyDemo,在main方法中,聲明創建每個子類的對象,并調用2個子類的showAll方法。package study;public abstract class Shape {    double area;    double per;//perimeter    String color;    public Shape() {            }    public Shape(String color) {        super();        this.color = color;    }    public abstract void getArea();    public abstract void getPer();    public abstract void showAll();    public String getColor() {        return color;    }    public void setColor(String color) {        this.color = color;    }        }package study;public class Rectangle extends Shape{    double length;    double width;    public Rectangle() {                }    public Rectangle(double a, double b,String c) {        super();        length=a;        width=b;        color=c;    }    @Override    public void getArea() {        // TODO Auto-generated method stub        area=length*width;    }    @Override    public void getPer() {        // TODO Auto-generated method stub        per=(length+width)*2;    }    @Override    public void showAll() {        // TODO Auto-generated method stub        System.out.println("顏色是"+color+"面積是"+area+"周長是"+per);            }    }package study;public class Circle extends Shape{    double radius;        public Circle() {            }    public Circle(double radius,String a) {        super();        this.radius = radius;        color=a;    }        @Override    public void getArea() {        // TODO Auto-generated method stub        area=radius*radius*3.14;    }    @Override    public void getPer() {        // TODO Auto-generated method stub        per=2*radius*3.14;    }    @Override    public void showAll() {        // TODO Auto-generated method stub        System.out.println("顏色是"+color+"半徑是"+radius+"面積是"+area+"周長是"+per);    }}package study;public class PolyDemo {    public static void main(String[] args) {        // TODO Auto-generated method stub        Rectangle r=new Rectangle(3,4,"月白");        r.getArea();        r.getPer();        r.showAll();        Circle c=new Circle(2.0,"橙黃");        c.getArea();        c.getPer();        c.showAll();    }}2、Cola公司的雇員分為以下若干類:(知識點:多態)(1) ColaEmployee :這是所有員工總的父類,屬性:員工的姓名,員工的生日月份。? 方法:getSalary(int month) 根據參數月份來確定工資,如果該月員工過生日,則公司會額外獎勵100 元。(2) SalariedEmployee :    ColaEmployee 的子類,拿固定工資的員工。? 屬性:月薪(3) HourlyEmployee :ColaEmployee 的子類,按小時拿工資的員工,每月工作超出160 小時的部分按照1.5 倍工資發放。? 屬性:每小時的工資、每月工作的小時數(4) Salesemployee :ColaEmployee 的子類,銷售人員,工資由月銷售額和提成率決定。? 屬性:月銷售額、提成率(5) 定義一個類Company,在該類中寫一個方法,調用該方法可以打印出某月某個員工的工資數額,寫一個測試類TestCompany,在main方法,把若干各種類型的員工放在一個ColaEmployee 數組里,并單元出數組中每個員工當月的工資。package Cola;public abstract class ColaEmployee {    String name;    int birthmonth;        public ColaEmployee() {            }    public ColaEmployee(String name, int birthmonth) {        this.name = name;        this.birthmonth = birthmonth;    }    abstract double getSalary(int month) ;}package Cola;public class SalariedEmployee extends ColaEmployee{    double salar;        public SalariedEmployee() {            }    public SalariedEmployee(String name, int birthmonth,double salar) {        super(name,birthmonth);        this.salar=salar;    }    @Override     double getSalary(int month) {        if(month==birthmonth) {            salar+=100;        }        return salar;    }}package Cola;public class HourlyEmployee extends ColaEmployee{    double shourly;    double hours;    public HourlyEmployee() {        super();        // TODO Auto-generated constructor stub    }    public HourlyEmployee(String name, int birthmonth,double shourly,double hours) {        super(name, birthmonth);        // TODO Auto-generated constructor stub        this.shourly=hours;        this.hours=hours;    }    double getSalary(int month) {        if(hours>160.0) {            shourly=(160.0*shourly)+(hours-160.0)*(shourly*1.5);        }else {            shourly=hours*shourly;        }        if(month==birthmonth) {            shourly+=100.0;            return shourly;        }else {            return shourly;        }    }}package Cola;public class SalesEmployee extends ColaEmployee{    double smonthly;    double rate;         public SalesEmployee() {        super();        // TODO Auto-generated constructor stub    }    public SalesEmployee(String name, int birthmonth, double smonthly,double rate) {        super(name, birthmonth);        // TODO Auto-generated constructor stub        this.smonthly=smonthly;        this.rate=rate;    }    public double getSalary(int month) {         smonthly=smonthly+smonthly*rate;         if(month==birthmonth) {             smonthly+=100;             return smonthly;         }else {             return smonthly;         }     }}package Cola;public class Company{    public static void getSalary(ColaEmployee a,int month) {        System.out.println(month+"月"+a.name+"員工"+"的月薪是"+a.getSalary(month)+"元。");    }}package Cola;public class TestCompany {    public static void main(String[] args) {        // TODO Auto-generated method stub        ColaEmployee [] b=new ColaEmployee[6];        b[0]=new SalesEmployee("王偉", 4, 10000, 5);        b[1]=new SalesEmployee("劉美",8,12000,5);        b[2]=new SalariedEmployee("張鈞", 11, 20000);        b[3]=new SalariedEmployee("高晟", 2, 23000);        b[4]=new HourlyEmployee("季澊", 9, 200, 168);        b[5]=new HourlyEmployee("沈復",5,300,170);        for (ColaEmployee a:b) {            Company.getSalary(a,5);        }    }}3、利用接口實現動態的創建對象:(知識點:接口 )(1)創建4個類    1蘋果    2香蕉    3葡萄    4園丁(2)在三種水果的構造方法中打印一句話.    以蘋果類為例    class apple    {        public apple()        {            System.out.println(“創建了一個蘋果類的對象”);    }    }(3)類圖如下:(4)要求從控制臺輸入一個字符串,根據字符串的值來判斷創建三種水果中哪個類的對象。    運行結果如圖:        package study;public interface Fruit {    }package study;public class apple implements Fruit {    public apple() {        super();        // TODO Auto-generated constructor stub        System.out.println("創建了一個蘋果類的對象");    }    }package study;public class Banana  implements Fruit {    public Banana() {        super();        // TODO Auto-generated constructor stub        System.out.println("創建了一個香蕉類的對象");    }    }package study;public class Pear  implements Fruit {    public Pear() {        super();        // TODO Auto-generated constructor stub        System.out.println("創建了一個梨類的對象");    }    }package study;import java.util.Scanner;public class Garder {     public void creater() {             System.out.println("請輸入你想創建的果園(蘋果,梨,香蕉):");            String s = "";            Scanner input = new Scanner(System.in);            s = input.nextLine();            if (s.equals("蘋果")) {                new apple();            } else if (s.equals("香蕉")) {                new Banana();            } else if (s.equals("梨")) {                new Pear();            } else {                System.out.println("請輸入正確的對象");            }        }}package study;public class Test {    public static void main(String[] args) {        // TODO Auto-generated method stub         new Garder().creater();                        }    }