IntStream findAny() with examples

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IntStream findAny() returns an OptionalInt (a container object which may or may not contain a non-null value) describing some element of the stream, or an empty OptionalInt if the stream is empty.

Syntax :

OptionalInt findAny()

Where, OptionalInt is a container object which
may or may not contain a non-null value 
and the function returns an OptionalInt describing some element of
this stream, or an empty OptionalInt 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 Integer Stream.

// Java code for IntStream findAny()
// which returns an OptionalInt describing
// some element of the stream, or an
// empty OptionalInt if the stream is empty.
import java.util.*;
import java.util.stream.IntStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an IntStream
        IntStream stream = IntStream.of(6, 7, 8, 9);
  
        // Using IntStream findAny() to return
        // an OptionalInt describing some element
        // of the stream
        OptionalInt answer = stream.findAny();
  
        // if the stream is empty, an empty
        // OptionalInt is returned.
        if (answer.isPresent()) {
            System.out.println(answer.getAsInt());
        }
        else {
            System.out.println("no value");
        }
    }
}

Output :

Note : The behavior of IntStream 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 IntStream findAny()
// which returns an OptionalInt describing
// some element of the stream, or an
// empty OptionalInt if the stream is empty.
import java.util.OptionalInt;
import java.util.stream.IntStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
  
        // Creating an IntStream
        IntStream stream = IntStream.of(4, 5, 8, 10, 12, 16)
                               .parallel();
  
        // Using IntStream findAny().
        // Executing the source code multiple times
        // may not return the same result.
        // Every time you may get a different
        // Integer which is divisible by 4.
        stream = stream.filter(num -> num % 4 == 0);
  
        OptionalInt answer = stream.findAny();
        if (answer.isPresent()) {
            System.out.println(answer.getAsInt());
        }
    }
}