如何在繼承的子類使用方法重載/方法覆蓋？

解決方法

此示例通過子類有不同數目和參數類型來說明方法重載的方法。

public class Findareas{
   public static void main (String []agrs){
      Figure f= new Figure(10 , 10);
      Rectangle r= new Rectangle(9 , 5);
      Figure figref;
      figref=f;
      System.out.println("Area is :"+figref.area());
      figref=r;
      System.out.println("Area is :"+figref.area());
   }
}
class Figure{
   double dim1;
   double dim2;
   Figure(double a , double b) {
      dim1=a;
      dim2=b;
   }
   Double area() {
      System.out.println("Inside area for figure.");
      return(dim1*dim2);
   }
}
class Rectangle extends Figure {
   Rectangle(double a, double b) {
      super(a ,b);
   }
   Double area() {
      System.out.println("Inside area for rectangle.");
      return(dim1*dim2);
   }
}

結果

上麵的代碼示例將產生以下結果。

Inside area for figure.
Area is :100.0
Inside area for rectangle.
Area is :45.0