Java LinkedList.pollFirst() is a method in the Java LinkedList class that retrieves and removes the first element of the list, or returns null if the list is empty. It is commonly used for dequeue operations in linked data structures. Introduced in Java 1997 with Java 1.2, pollFirst() is often used in FIFO queue implementations where elements need to be processed in the order they were added.

https://docs.oracle.com/javase/8/docs/api/java/util/LinkedList.html