circle2.java

可以让初学者有一个感性的认识

import java.io.*;

public class Circle2
{
	double radius=1;
	double circleArea=0;
	double circleLength=0;

	public double getRadius(){return radius;}

	public void setRadius(double newRadius){radius=newRadius;}

	public double getCircleArea()
	{
		circleArea=Math.PI*radius*radius;
		return circleArea;
	}

	public double getCircleLength()
	{	
		circleLength=2.0*Math.PI*radius;
		return circleLength;
	}
}