IntStream iterate in steps
Actually range
is ideal for this.
IntStream.range(0, 100).filter(x -> x % 3 == 0); //107,566 ns/op [Average]
Edit: Holgers's solution is the fastest performing solution.
Since the following lines of code
IntStream.range(0, 100).filter(x -> x % 3 == 0).forEach((x) -> x = x + 2);
IntStream.range(0, 100 / 3).map(x -> x * 3).forEach((x) -> x = x + 2);
int limit = ( 100 / 3 ) + 1;
IntStream.iterate(0, n -> n + 3).limit(limit).forEach((x) -> x = x + 2);
show these benchmark results
Benchmark Mode Cnt Score Error Units
Benchmark.intStreamTest avgt 5 485,473 ± 58,402 ns/op
Benchmark.intStreamTest2 avgt 5 202,135 ± 7,237 ns/op
Benchmark.intStreamTest3 avgt 5 280,307 ± 41,772 ns/op
Actually you can also achieve the same results with a combination of peek and allMatch:
IntStream.iterate(0, n -> n + 3).peek(n -> System.out.printf("%d,", n)).allMatch(n -> n < 100 - 3);
This prints
0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60,63,66,69,72,75,78,81,84,87,90,93,96,99,
But nevertheless, this one is faster:
IntStream.range(0, 100 / 3 + 1).map(x -> x * 3).forEach((x) -> System.out.printf("%d,", x));
Java 9 Update:
Now the same iteration easier to achieve with Java 9:
Stream.iterate(0, i -> i <= 100, i -> 3 + i).forEach(i -> System.out.printf("%d,", i));
In JDK9 there's takeWhile
1
IntStream
.iterate(0, n -> n + 3)
.takeWhile(n -> n < 100)
.forEach(System.out::println);