LongStream findAny() returns an OptionalLong (a container object which may or may not contain a non-null value) describing some element of the stream, or an empty OptionalLong if the stream is empty.
Syntax :
OptionalLong findAny()
Parameters :
- OptionalLong : A container object which may or may not contain a non-null value.
Return Value : The function returns an OptionalLong describing some element of this stream, or an empty OptionalLong if the stream is empty.
Note : findAny() is a terminal-short-circuiting operation of Stream interface. This method returns any first element satisfying the intermediate operations. This is a short-circuit operation because it just needs ‘any’ first element to be returned and terminate the rest of the iteration.
Example 1 : findAny() method on Long Stream.
// Java code for LongStream findAny()// which returns an OptionalLong describing// some element of the stream, or an// empty OptionalLong if the stream is empty.import java.util.*;import java.util.stream.LongStream; class GFG { // Driver code public static void main(String[] args) { // Creating an LongStream LongStream stream = LongStream.of(6L, 7L, 8L, 9L); // Using LongStream findAny() to return // an OptionalLong describing some element // of the stream OptionalLong answer = stream.findAny(); // if the stream is empty, an empty // OptionalLong is returned. if (answer.isPresent()) { System.out.println(answer.getAsLong()); } else { System.out.println("no value"); } }} |
Output :
6
Note : The behavior of LongStream findAny() operation is explicitly non-deterministic i.e, it is free to select any element in the stream. Multiple invocations on the same source may not return the same result.
Example 2 : findAny() method to return the elements divisible by 4, in a non-deterministic way.
// Java code for LongStream findAny()// which returns an OptionalLong describing// some element of the stream, or an// empty OptionalLong if the stream is empty.import java.util.OptionalLong;import java.util.stream.LongStream; class GFG { // Driver code public static void main(String[] args) { // Creating an LongStream LongStream stream = LongStream.of(4L, 5L, 8L, 10L, 12L, 16L) .parallel(); // Using LongStream findAny(). // Executing the source code multiple times // may not return the same result. // Every time you may get a different // value which is divisible by 4. stream = stream.filter(num -> num % 4 == 0); OptionalLong answer = stream.findAny(); if (answer.isPresent()) { System.out.println(answer.getAsLong()); } }} |
Output :
16
