Java - implementing ConcurrentModificationException When Filtering Collections with Java 8 Streams
I tried several approaches but none seem to work... I'm working with a `ConcurrentModificationException` when trying to filter a list while also modifying it in another part of my code. I'm using Java 8 streams for filtering, and I have a situation where I need to remove elements from a list based on a condition while iterating through it. Here’s a simplified version of my code: ```java import java.util.ArrayList; import java.util.List; import java.util.stream.Collectors; public class FilterExample { public static void main(String[] args) { List<Integer> numbers = new ArrayList<>(); for (int i = 0; i < 10; i++) { numbers.add(i); } // Attempting to remove elements while filtering List<Integer> filteredNumbers = numbers.stream() .filter(num -> { if (num % 2 == 0) { numbers.remove(num); // This line causes ConcurrentModificationException } return num % 2 != 0; }) .collect(Collectors.toList()); System.out.println(filteredNumbers); } } ``` When I run this, I receive the following behavior: ``` Exception in thread "main" java.util.ConcurrentModificationException ``` I’ve read that modifying a collection while iterating over it can lead to this behavior, but I thought using streams would handle it differently. I've tried using an `Iterator` to remove elements instead, but that adds unnecessary complexity to my code. Is there a cleaner way to achieve this filtering and removal without running into `ConcurrentModificationException`? Also, are there any best practices for filtering and modifying collections in this way in Java 8? I'm working in a Windows 10 environment. What are your experiences with this?