Priority queue with level-based notification in Java

Question

Is there a kind of PriorityBlockingQueue in Java that allows waiting (like the take() method does) for a certain level of elements instead of one element? Ie "notify me when the level reaches 500 elements"?

Answer 1

Is there a kind of BlockingPriorityQueue in Java that allows waiting (like the take() method does) for a certain level of elements instead of one element?

No . There is a PriorityBlockingQueue

Answer 2

No you don't have maybe you can extend PriorityBlockingQueue for your need. take() can return once you have more than 500 elements.

private volatile size;

public synchronized void take(){
      while(size<500){
        ........
        .........
      }
}

just pseudocode.