Find first element by predicate

by

No, filter does not scan the whole stream. It’s an intermediate operation, which returns a lazy stream (actually all intermediate operations return a lazy stream). To convince you, you can simply do the following test:

List<Integer> list = Arrays.asList(1, 10, 3, 7, 5);
int a = list.stream()
            .peek(num -> System.out.println("will filter " + num))
            .filter(x -> x > 5)
            .findFirst()
            .get();
System.out.println(a);

Which outputs:

will filter 1
will filter 10
10

You see that only the two first elements of the stream are actually processed.

So you can go with your approach which is perfectly fine.

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