public abstract class TwoDShape implements MyComparable {

  public final boolean isLarger(MyComparable other) throws InvalidComparableTypeException {
    if( other instanceof TwoDShape ) {
      TwoDShape obj = (TwoDShape)other;
      if( this.getArea() > obj.getArea() ) 
        return true;
      else 
        return false;
     }
     throw new InvalidComparableTypeException();
  }
  
  public final boolean isEqual(MyComparable other) throws InvalidComparableTypeException {
    if( other instanceof TwoDShape ) {
      TwoDShape obj = (TwoDShape)other;
      if( this.getArea() == obj.getArea() ) 
        return true;
      else 
        return false;
    }
    throw new InvalidComparableTypeException();
  }
  
  public abstract double getArea();
}