Java 8 FAQ: Top Questions

The forEach() method is a terminal operation in Java 8 Streams that performs an action on each element of the stream. It is commonly used to print or apply a side-effect on elements of a stream.

🗺️ Step-by-Step Instructions:

1. Use forEach() at the end of a stream pipeline.
2. Pass a Consumer lambda to define the action for each element.
3. This method does not return a result and is considered side-effecting.

📥 Example Input:

List names = Arrays.asList("Java", "Python", "C++");

names.stream()
     .forEach(name -> System.out.println("Language: " + name));

🏆 Expected Output:

Language: Java
Language: Python
Language: C++

✅ Java 8 Solution:

import java.util.*;
import java.util.stream.*;

public class StreamForEachExample {
  public static void main(String[] args) {
    List names = Arrays.asList("Java", "Python", "C++");

    names.stream()
         .forEach(name -> System.out.println("Language: " + name));
  }
}

📘 Detailed Explanation:

• forEach(): Applies a Consumer to each stream element.
• Terminal operation: Ends the stream pipeline.
• Side-effects: Used for logging, printing, or updating external state (use with care).

🛠️ Use Cases:

• Displaying or logging stream contents.
• Applying non-transforming operations like metrics or counters.
• Iterating over filtered or mapped results directly.