JAVA EXAMPLE PROGRAMS

JAVA EXAMPLE PROGRAMS

Publish Your Article Here

Java 8 Stream peek method example.


The Stream.peek() method is mainly to support debugging, where you want to see the elements as they flow past a certain point in a pipeline.

The Stream.peek() method returns a stream consisting of the elements of this stream, additionally performing the provided action on each element as elements are consumed from the resulting stream.

For parallel stream pipelines, the action may be called at whatever time and in whatever thread the element is made available by the upstream operation. If the action modifies shared state, it is responsible for providing the required synchronization.

package com.java2novice.streams;

import java.util.stream.Collectors;
import java.util.stream.Stream;

public class StreamPeekEx {

	public static void main(String a[]) {

		Stream.of("bus", "car", "bycle", "flight", "train")
		        .filter(e -> e.length() > 3)
		        .peek(e -> System.out.println("Filtered value: " + e))
		        .map(String::toUpperCase)
		        .peek(e -> System.out.println("Mapped value: " + e))
		        .collect(Collectors.toList());
	}
}

Output:
Filtered value: bycle
Mapped value: BYCLE
Filtered value: flight
Mapped value: FLIGHT
Filtered value: train
Mapped value: TRAIN
<< Previous Program | Next Program >>

Java 8 Streams Examples

  1. How Java 8 Streams work?
  2. Java 8 Streams parallelism introduction.
  3. Explain non-interference behavior of Java 8 Streams.
  4. Create Java 8 Stream using Stream.of() method example.
  5. Create Java 8 Stream using List example.
  6. Create Java 8 Stream using Stream.generate() method.
  7. Java 8 Stream.filter() example.
  8. Java 8 Stream.map() example.
  9. Java 8 Stream flatmap method example.
  10. Java 8 Stream peek method example.
  11. Java 8 Stream distinct method example.
  12. Java 8 Stream sorted method example.
  13. Java 8 Stream limit method example.
  14. Java 8 Stream forEach method example.
  15. Java 8 Stream toArray method example.
  16. Java 8 Stream reduce method example.
  17. Java 8 Stream collect method example.
  18. Java 8 Stream concat method example.
  19. Java 8 Stream anyMatch(), allMatch() and noneMatch() example.
  20. Java 8 Stream findFirst(), findAny() example.
  21. Primitive type Stream example.
Knowledge Centre
Where can we use serialization?
Whenever an object has to sent over the network, those objects should be serialized. Also if the state of an object is to be saved, objects need to be serilazed.
Famous Quotations
If you don’t make mistakes, you’re not working on hard enough problems. And that’s a big mistake.
-- Frank Wilczek

About Author

I'm Nataraja Gootooru, programmer by profession and passionate about technologies. All examples given here are as simple as possible to help beginners. The source code is compiled and tested in my dev environment.

If you come across any mistakes or bugs, please email me to [email protected].

Most Visited Pages

Other Interesting Sites

Reference: Java™ Platform Standard Ed. 7 - API Specification | Java™ Platform Standard Ed. 8 - API Specification | Java is registered trademark of Oracle.
Privacy Policy | Copyright © 2022 by Nataraja Gootooru. All Rights Reserved.