testshape.java

3． 设计一个接口Shape

interface shape

{
 abstract void draw();
 abstract void resize();	
}

class point implements shape

{
  private int x;
  private int y;
  
  public void draw()
  {
   System.out.println("the point zuobiao is("+x+","+y+")");
  }
  	
  public void resize()
  {
   System.out.println("point turn big")	;
  }
  
  public point(int x,int y)	
  {
  	this.x=x;
  	this.y=y;
  }
  
} 

class line implements shape
{
  private  int x1;
  private  int y1;
  private  int x2;
  private  int y2;
  
  public void draw()
  {
  System.out.println("the line first point is ("+x1+","+y1+")second point is:("+x2+","+y2+")");
  }	
  public void resize()
  {
  	System.out.println("line turn big");
  }
  public line(int a,int b,int c,int d)
  {
   x1=a;y1=b;x2=c;y2=d;	
  }
  
}

class circle implements shape
{
 private int x;
 private int y;
 private int width;
 private int height;
 private double r;
 
 public void draw()
 {
 System.out.println("the circle point zuobiao is("+x+","+y+")");
 System.out.println("the circle radus:"+r);
 }	
 public void resize()
 {
  System.out.println("circle turn big");
 }
 
 public circle(int a,int b,int c,int d)	
 {
  x=a;
  y=b;
  width=c;
  height=d;
  r=(double)width/2;
 }

}

class rectangle implements shape
{
 private int x;
 private int y;
 private int width;
 private int height;
 
 public void draw()
 {
  	System.out.println("the rectangle's left zuobiao is:("+x+","+y+")"); 
  	System.out.println("the rectangel's width and height is :("+width+","+height+")");
 }
 public void resize()
 {
 	System.out.println("rectangle turn big");
 }
 
 public rectangle(int a,int b,int c,int d)	
 {
  x=a;
  y=b;
  width=c;
  height=d;	
 }

}

public class testshape 
{
 public static void main(String args[])	
 {
  point p1=new point(3,5);
  line p2=new line(3,4,20,30);
  circle p3=new circle(10,20,20,20);
  rectangle p4=new rectangle(10,5,50,30);
  p1.draw();
  p1.resize();
  p2.draw();
  p2.resize();
  p3.draw();
  p3.resize();
  p4.draw();
  p4.resize();
 }
}