Processing usernames for display
In a user management system, we need to display usernames stored in a database. Using Streams
and .forEach()
, we can efficiently process and print each username without using traditional loops.
This exercise is part of the course
Input/Output and Streams in Java
Exercise instructions
- Convert the
usernames
list into aStream
object. - Print each element in the
stream
using a lambda expression.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
import java.util.List;
import java.util.ArrayList;
import java.util.stream.Stream;
public class UserDisplay {
public static void main(String[] args) {
List usernames = new ArrayList<>();
usernames.add("Alice123");
usernames.add("BobTheCoder");
usernames.add("CharlieDev");
usernames.add("David99");
// Convert list to Stream
Stream stream = usernames.____();
// Print each username
stream.____(name -> System.out.println("User: " + name));
}
}