PriorityQueue poll() Method in Java
The java.util.PriorityQueue.poll() method in Java is used to retrieve or fetch and remove the first element of the Queue or the element present at the head of the Queue. The peek() method only retrieved the element at the head but the poll() also removes the element along with the retrieval. It returns NULL if the queue is empty.
Parameters: The method does not take any parameters.
Return Value: The method returns the element at the head of the Queue else returns NULL if the Queue is empty.
Below programs illustrate the use of java.util.PriorityQueue.poll() method:
Initial PriorityQueue: [For, Geeks, To, Welcome, Geeks] The element at the head of the queue is: For Final PriorityQueue: [Geeks, Geeks, To, Welcome]
Initial PriorityQueue: [5, 10, 30, 20, 15] The element at the head of the queue is: 5 Final PriorityQueue: [10, 15, 30, 20]