DoubleStream findAny() returns an OptionalDouble (a container object which may or may not contain a non-null value) describing some element of the stream, or an empty OptionalDouble if the stream is empty.
Syntax :
OptionalDouble findAny()
Parameters :
- OptionalDouble : A container object which may or may not contain a non-null value.
Return Value : The function returns an OptionalDouble describing some element of this stream, or an empty OptionalDouble 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 Double Stream.
// Java code for DoubleStream findAny() // which returns an OptionalDouble describing // some element of the stream, or an // empty OptionalDouble if the stream is empty. import java.util.*; import java.util.stream.DoubleStream; class GFG { // Driver code public static void main(String[] args) { // Creating an DoubleStream DoubleStream stream = DoubleStream.of( 6.3 , 7.4 , 8.5 , 9.6 ); // Using DoubleStream findAny() to return // an OptionalDouble describing some element // of the stream OptionalDouble answer = stream.findAny(); // if the stream is empty, an empty // OptionalDouble is returned. if (answer.isPresent()) { System.out.println(answer.getAsDouble()); } else { System.out.println( "no value" ); } } } |
Output :
6.3
Note : The behavior of DoubleStream 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 DoubleStream findAny() // which returns an OptionalDouble describing // some element of the stream, or an // empty OptionalDouble if the stream is empty. import java.util.OptionalDouble; import java.util.stream.DoubleStream; class GFG { // Driver code public static void main(String[] args) { // Creating an DoubleStream DoubleStream stream = DoubleStream.of( 4.4 , 5.6 , 8.4 , 10.2 , 12.0 , 16.0 ).parallel(); // Using DoubleStream findAny(). // Executing the source code multiple times // may not return the same result. // Every time you may get a different // Double value which is divisible by 4. stream = stream.filter(num -> num % 4 == 0 ); OptionalDouble answer = stream.findAny(); if (answer.isPresent()) { System.out.println(answer.getAsDouble()); } } } |
Output :
16.0