java2.java

各种计算功能的实现

import java.lang.StrictMath;
abstract class Shape extends Object{
	double xPos;
	double yPos;

	public Shape(){
		xPos=0;
		yPos=0;
	}

	public Shape(double x,double y){
		xPos=x;
		yPos=y;
	}

	abstract public double area();
    abstract public void stretchBy(double factor);
	abstract public void printScr();
	public final double getXPos(){
		return xPos;
	}
	public final double getYPos(){
		return yPos;
	}

}
class Rect extends Shape{
	double width;
	double height;

	Rect(double x,double y,double w,double h){
		super(x,y);
		width=w;
		height=h;
	}


	public void stretchBy(double factor){
		width=width*factor;
		height=height*factor;
		};


	public double area(){
		double area=width*height;
		return area;

     }

     public void printScr(){
    	String str;
    	str="RECTANAGLE\n";
    	str+="(X,Y)Position:("+super.getXPos()+","+super.getYPos()+")\n";;
    	str+="Width & Height:"+width+" & "+height+"\n";
    	str+="Area:"+area()+"\n";
    	System.out.println(str);
     }
}

class Circle extends Shape{
	double radius;

	Circle(double x,double y,double r){
		super(x,y);
        radius=r;
	}

	public void stretchBy(double factor){
		radius=radius*factor;
		}

	public double area(){
		double area=StrictMath.PI*radius*radius;
		return area;

     }
    public double Girth(){
     	double girth=2*StrictMath.PI*radius;
     	return girth;
     	}

    public void printScr(){
    	String str;
    	str="CIRCLE\n";
    	str+="(X,Y)Position:("+super.getXPos()+","+super.getYPos()+")\n";;
    	str+="Radius:"+radius+"\n";
    	str+="Area:"+area()+"\n";
     	System.out.println(str);
     }
}

class Cylinder extends Circle{
	double zPos;
	double height;

	Cylinder(double x,double y,double z,double r,double h){
		super(x,y,r);
		zPos=z;
		height=h;
	}

	public void stretchBy(double factor){
		radius=radius*factor;
		height=height*factor;
		}

	public double area(){
		double area=2*super.area()+super.Girth()*height;
		return area;

     }
     public double Volume(){
     	double volume=super.area()*height;
     	return volume;
     }


     public void printScr(){
    	String str;
    	str="CYLINDER\n";
    	str+="(X,Y,Z)Position:("+super.getXPos()+","+super.getYPos()+","+zPos+")\n";;
    	str+="Radius & Height:"+radius+" & "+height+"\n";
    	str+="Area:"+area()+"\n";
        str+="Volume:"+Volume();
        System.out.println(str);
     }
}


class TestShape{


	public static void main(String args[]){
		Shape[] sha=new Shape[3];
		sha[0]=new Circle(1.0,2.0,1.0);
		sha[1]=new Rect(1.0,2.0,2.0,1.0);
		sha[2]=new Cylinder(1.0,2.0,3.0,1.0,2.0);
		System.out.println("Before stretching....\n");
		sha[0].printScr();
		sha[1].printScr();
		sha[2].printScr();
		sha[0].stretchBy(2.0);
		sha[1].stretchBy(2.0);
		sha[2].stretchBy(2.0);
		System.out.println("\n");
		System.out.println("After stretched....\n");
		sha[0].printScr();
		sha[1].printScr();
		sha[2].printScr();

	}
	}




//////////////////////////////////////////////////////////////////////////////////
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abstract class Shape extends Object{
  private double xPos;
  private double yPos;

  public Shape(){
    xPos = 0;
    yPos = 0;
  }

  abstract public double area();

  abstract public void strethBy(double factor);

  public final double getXpos(){
    return xPos;
  }

  public final double getYpos(){
    return yPos;
  }

  public void moveTo (double xLoc,double yLoc){
    xPos = xLoc;
    yPos = yLoc;
  }

  public String toString(){
    String str = "(X,Y)Position:("+ xPos +","+ yPos +")\n";
    return str;
  }
}
public class Circle extends Shape(){
  private R;
  final double Pi=3.141592653589793;

  public Circle(double r){
    super();
    R = r;
  }

  public Circle(double x,double y, double r){
    super  (x,y);
    R = r;
  }

  public double area(){
    return R*R*Pi;
  }

  public void strechBy(double factor){
    R = R*factor;
  }

  public String toString(){
    String str1=super.toString()+"Radius:"+R+"\n"+"Area:"+area()+"\n";
    return str1;
  }

public class Rectangle extends Shape(){
  private W,H;
  public Rectangle (double w,double h){
    super();
    W = w;
    H = h;
  }

  public Rectangle(double x,double y,double w ,double h){
    super(x,y);
    W = w;
    H = h;
  }

  public double area(){
    return W*H;
  }

  public void strethBy(double factor){
    return W = factor*W,H = factor*H;
  }

  public String toString(){
     String str1=super.toString()+"width:"+W+"\n"+"high:"+H+"area:"+area()+"\n";
  }
}