calculatearea.java

来自「一些相关的JAVA小实例」· Java 代码 · 共 40 行

abstract class shape{
	 double length;
	 double width;
	shape(double num,double num1){
		length=num;
		width=num1;
	}
	abstract double area();
}
class square extends shape{
	square(double num,double num1){
		super(num,num1);
	}
double area(){
	System.out.print("正方形面积为： ");
	return (length*width);
}
}
class triangle extends shape{
	triangle(double num,double num1){
		super(num,num1);
	}
	double area(){
	System.out.print("三角形面积为： ");
	return(length*width/2);
	}
}
public class calculatearea{
	protected calculatearea(){
	}
	public static void main(String[] s){
		shape fobj;
		square   sqobj=new square(10,20);
		triangle trobj=new triangle(12,8);
		fobj=sqobj;
		System.out.println(fobj.area());
		fobj=trobj;
		System.out.println(fobj.area());
	}
}