Is there a better way to fill an ArrayList like this (I have done it like this in Java 7):
List<ScheduleIntervalContainer> scheduleIntervalContainers = new ArrayList<>();
scheduleIntervalContainers.add(scheduleIntervalContainer);
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1What's wrong with that way? – Eran Oct 15 '15 at 05:28
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I'm not aware of a way, but Java 8 features are not something I have a lot of expertise in. But when I look at your code, the only thing that makes it look long and cumbersome are long variable names. Personally I wouldn't shorten those either because I'd rather long descriptive names and self documenting code over brevity and so will anyone who has to maintain the code. – Sammy Oct 15 '15 at 05:40
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2`List
scheduleIntervalContainers = new ArrayList<>(Arrays.asList(scheduleIntervalContainer));` – Alexis C. Oct 15 '15 at 08:45 -
2@Alexis C.: for a single element list, there is `Collections.singletonList(…))` which spares you from creating an array… – Holger Oct 15 '15 at 09:22
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3It’s not clear what you are asking. You talk about “filling” but are actually only adding a single element. What better way to add a single element to a list than invoking a method named `add` on that list can you imagine? – Holger Oct 15 '15 at 09:24
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To fill a List, it is possible to generate an infinite Stream using Stream.generate(s) and then limit the number of results with limit(maxSize).
For example, to fill a List of 10 new ScheduleIntervalContainer objects:
List<ScheduleIntervalContainer> scheduleIntervalContainers =
Stream.generate(ScheduleIntervalContainer::new).limit(10).collect(toList());
The generate method takes a Supplier: in this case, the supplier is a method reference creating new instance of ScheduleIntervalContainer each time.
Tunaki
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