14.3

 1 import java.awt.*;
 2 import java.util.Scanner;
 3 
 4 import javax.swing.*;
 5 
 6 public class Test{
 7   public static void main(String[] args){
 8       GeometricObject g1 = new Square();
 9       GeometricObject g2 = new Square("yellow", 1,true);
10       
11       if(((Square)g1).filled)      
12       {System.out.println("g1:");
13           ((Square)g1).howToColor();}
14       
15       if(((Square)g2).filled)
16       {System.out.println("g2:");
17           ((Square)g2).howToColor();}
18   }  
19 }
Test.java
public interface Colorable {
    abstract void howToColor();
}
Colorable.java
 1 // GeometricObject.java: The abstract GeometricObject class
 2 public class GeometricObject implements Comparable{
 3   protected String color = "white";
 4   protected boolean filled;
 5   protected int a;
 6 
 7   /**Default construct*/
 8   protected GeometricObject() {
 9       filled = false;
10   }
11 
12   /**Construct a geometric object*/
13   protected GeometricObject(String color, int a,boolean filled) {
14     this.color = color;
15     this.a = a;
16     this.filled = filled;
17   }
18 
19   public static Comparable max(Comparable c1,Comparable c2){
20       if(c1.compareTo(c2)>0)
21       return c1;
22       else return c2;
23   }
24   public int compareTo(Object o){
25       if(this.getArea() > ((GeometricObject)o).getArea())
26           return 1;
27       else if (this.getArea() == ((GeometricObject)o).getArea())
28           return 0;
29       else return -1;
30   }
31   /**Getter method for color*/
32   public String getColor() {
33     return color;
34   }
35 
36   /**Setter method for color*/
37   public void setColor(String color) {
38     this.color = color;
39   }
40 
41   /**Getter method for filled. Since filled is boolean,
42      so, the get method name is isFilled*/
43   public boolean isFilled() {
44     return filled;
45   }
46 
47   /**Setter method for filled*/
48   public void setFilled(boolean filled) {
49     this.filled = filled;
50   }
51 
52   /**Abstract method findArea*/
53   public  int getArea(){
54       return a*a;
55   }
56 
57   /**Abstract method getPerimeter*/
58   public  double getPerimeter(){
59       return 1;
60   }
61 }
GeometricObject.java
 1 public class Square extends GeometricObject implements Colorable{
 2 
 3     public Square() {
 4         // TODO Auto-generated constructor stub
 5     }
 6 
 7     protected Square(String color, int a,boolean filled) {
 8         this.color = color;
 9         this.a = a;
10         this.filled = filled;
11       }
12     @Override
13     public void howToColor() {
14         // TODO Auto-generated method stub
15         System.out.println("Color all four sides");
16     }
17 
18 }
Square.java

 

posted on 2016-06-16 10:20  功夫茶茶  阅读(118)  评论(0编辑  收藏  举报

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