circle.java

来自「this sourse code for the hw problems in 」· Java 代码 · 共 22 行

class Circle extends GeoFigure{
	protected double rd;
	Circle (double r){
		this.rd=r;
	}
	public double getRadius(){
		return rd;
	}
	public void setRadius(double r){
		this.rd=r;
	}
	public double computeArea() { 
		return (Math.PI*rd*rd);
	}
	public double computePerimeter() {
		return (2*Math.PI*rd);
	}
	public String toString(){
		return "Circle: " + rd;
	}
}