public class Box3D {
   Box3D () { length = 1; width = 1; height = 1; }
   Box3D (float length, float width, float height) { this.length = length; this.width = width; this.height = height; }

   float volume() { return length * width * height; }
   float surfaceArea() { return 2 * (length * width + width * height + length * height); }

   public String toString() { return "[length=" + length + ",width=" + width + ",height=" + height + "]"; }

   private float length, width, height;
}