public class Box extends Rectangle
{
    private int depth;

    public Box(int theWidth, int theHeight, int theDepth)
    {
        // Call base class constructor.
        super(theWidth, theHeight);

        // Only nonnegative depth is allowed
        if (theDepth > 0)
            depth = theDepth;
        else
            depth = 0;
    }

    public int getVolume( )
    {
        return depth * getArea( );
    }

    public String toString( )
    {
        String temp = super.toString( );
        int index = temp.indexOf(" area");
        temp = temp.substring(0, index);
        return String.format("%sx%d volume=%d",
            temp, depth, getVolume( ));
    }

    public static void main(String[ ] args)
    {
        Box r = new Box(12, 15, 10);
        System.out.println("Volume of r is " + r.getVolume( ));
        System.out.println("toString output of r is ");
        System.out.println(r);
        System.out.println(r);

        // Test behavior of negative depth in constructor.
        System.out.println(new Box(-5, 15, 10));
        System.out.println(new Box(12, -8, 10));
        System.out.println(new Box(-5, -8, 10));
        System.out.println(new Box(-5, 15, -3));
        System.out.println(new Box(12, -8, -3));
        System.out.println(new Box(-5, -8, -3));



    }

}