patocskaierik / decrementing-carousel-with-limit

Decrementing Carousel With Limit

The purpose of this exercise is to train you to use extend classes with extends keyword.

Estimated workload of this exercise is 30 min.

Note, that if you have not done the "Decrementing Carousel" exercise, you have to implement DecrementingCarousel and CarouselRun classes. Details are specified in DC.md.

Description

In this exercise you need to extend DecrementingCarousel. You need to implement DecrementingCarouselWithLimitedRun. This subclass must decrement elements as a usual DecrementingCarousel. The difference is that this implementation must produce a carousel run, which limits number of calls to the next method. When the limit of calls reached carousel run must consider itself finished.

Examples

Empty case:

CarouselRun run = new DecrementingCarouselWithLimitedRun(7, 5).run();
System.out.println(run.isFinished()); //true
System.out.println(run.next()); //-1

Regular case:

DecrementingCarousel carousel = new DecrementingCarouselWithLimitedRun(7, 10);

carousel.addElement(20);
carousel.addElement(30);
carousel.addElement(10);

CarouselRun run = carousel.run();

System.out.println(run.isFinished()); //false

System.out.println(run.next()); //20
System.out.println(run.next()); //30
System.out.println(run.next()); //10

System.out.println(run.next()); //19
System.out.println(run.next()); //29
System.out.println(run.next()); //9

System.out.println(run.next()); //18
System.out.println(run.next()); //28
System.out.println(run.next()); //8

System.out.println(run.next()); //17

System.out.println(run.isFinished()); //true
System.out.println(run.next()); //-1