The PriorityQueue.poll() method is used to retrieve and remove the element at the head of the Queue. This method returns null if the Queue is empty. It is important to note that this method only guarantees that the lowest or highest priority element will be at the head of the queue and not necessarily in its original order. The poll() function runs in linearithmic (O(n log n)) time with respect to data structure size, making it a useful tool for tasks such as computing aggregate values quickly and efficiently.
2. Why We Need Poll From Queue In Priority Queue
The PriorityQueue.poll() method of the PriorityQueue is used to retrieve and remove the head element of a queue. This method ensures that the element with the highest priority in the queue will be retrieved first. It is useful when we need to process messages in a particular order, as it guarantees that elements are processed according to their priority level. Additionally, it provides a non-thread-safe queue with dequeue order which is not possible with regular queues. Therefore, when you need to process elements from a queue based on their priority, then you can use PriorityQueue.poll() from PriorityQueue for this purpose.
3. Implementation Poll In Priority Queue
Polling from a PriorityQueue can be very beneficial, as it allows us to prioritize tasks based on their importance. By constantly serving up the next event to be processed, the PriorityQueue ensures that important tasks are completed first. Implementing the priority queue pattern is easy in a polling environment: all we have to do is register methods for our resources and they become responsible for polling the queue for their next task.