Optional stream() method in Java with examples
Last Updated :
12 Jul, 2025
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The stream() method of java.util.Optional class in Java is used to get the sequential stream of the only value present in this Optional instance. If there is no value present in this Optional instance, then this method returns returns an empty Stream.
Syntax:
Java
Output:
Java
Output:
public Stream<T> stream()Parameters: This method do not accept any parameter. Return value: This method returns the sequential stream of the only value present in this Optional instance. If there is no value present in this Optional instance, then this method returns an empty Stream. Below programs illustrate stream() method: Note: Below programs require JDK 9 and above to execute. Program 1:
// Java program to demonstrate
// Optional.stream() method
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create a Optional
Optional<Integer> op
= Optional.of(9455);
// print value
System.out.println("Optional: "
+ op);
// get the Stream
System.out.println("Getting the Stream:");
op.stream().forEach(System.out::println);
}
}
Optional: Optional[9455] Getting the Stream: 9455Program 2:
// Java program to demonstrate
// Optional.stream() method
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create a Optional
Optional<Integer> op
= Optional.empty();
// print value
System.out.println("Optional: "
+ op);
try {
// get the Stream
System.out.println("Getting the Stream:");
op.stream().forEach(System.out::println);
}
catch (Exception e) {
System.out.println(e);
}
}
}
Optional: Optional.empty Getting the Stream:Reference: https://docs.oracle.com/javase/9/docs/api/java/util/Optional.html#stream--
