A Queue that ensure uniqueness of the elements?

Question

I\'m looking for a implementation of java.util.Queue or something in the Google collection who behave like a Queue, but also ensure that each element of the queue is unique.

Answer 1

Unfortunately it doesn't exist. Since I needed such a Queue I have developed a Blocking Queue backed by a set, inspired by java.util.concurrent.LinkedBlockingQueue.

You can find it here :

https://github.com/bvanalderweireldt/concurrent-unique-queue

Example :

final BlockingQueue queue = new ConcurrentSetBlockingQueue<>(1);
queue.offer(new Integer(1)); //True
queue.offer(new Integer(1)); //False

You can use it with Maven :

  com.hybhub
  concurrent-util
  0.1