public abstract class Shape
{
    abstract public double area( );

    public Shape( String shapeName )
    {
        name = shapeName;
    }

    final public boolean lessThan( Shape rhs )
    {
        return area( ) < rhs.area( );
    }

    final public String toString( )
    {
        return name + " of area " + area( );
    }

    private String name;
}