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
