shape.java

Java程序设计技巧与开发实例附书源代码。

public abstract class Shape
{
   protected String type;
   protected double area, perim;
   public abstract void computeArea();

   public abstract void computePerimeter();

   public String toString()
   {
      return type + ":\n\tArea = " + area + "\n\tPerimeter = " + perim;
   }
}