public class ShapeTester
{ public static void main(String args[])
{ Shape s=new Shape();
Rectangle r=new Rectangle(2.0,3.0);
Circle c=new Circle(4.0);
r.computeArea();
r.computePeremeter();
c.computeArea();
c.computePeremeter();
r.display();c.display();s.display();
}
}
class Shape
{ protected String name;
protected double area,peremeter;
public Shape()
{ name="undermined";
area=peremeter=0;
}
public void display()
{ System.out.println("Name:"+name);
System.out.println("Area;"+area);
System.out.println("peremeter:"+peremeter);
}
}
class Rectangle extends Shape
{ protected double length,width;
protected Rectangle(double _length,double _width)
{ name="Rectangle";
length=_length;
width=_width;
}
public void computeArea()
{ area=length*width; }
public void computePeremeter()
{ peremeter=2*(length+width); }
}
class Circle extends Shape
{ protected double radius;
protected Circle(double _radius)
{ name="Circle";
radius=_radius;
}
public void computeArea()
{ area=Math.PI*radius*radius;}
public void computePeremeter()
{ peremeter=2*Math.PI*radius;}
}
调不出来，大家帮忙看下，貌似没啥问题啊！
------解决方案--------------------
什么调不出来，貌似没啥问题
------解决方案--------------------
经测试，程序无问题能正确运行！注意下是不是文件名字与public声明的类名字一样（你这程序名字应为：ShapeTester.java）结果如下：
Name:Rectangle
Area;6.0
peremeter:10.0
Name:Circle
Area;50.26548245743669
peremeter:25.132741228718345
Name:undermined
Area;0.0
------解决方案--------------------