Queue

The last in line is the Queue interface. It’s part of the Java collections framework and allows FIFO data storage. The head of the queue is the oldest element, and the tail is the newest element. Queues are useful for processing tasks in the order they are received. There is also a sub-interface called Deque, which is a special type of queue that allows you to get elements from both the head and the tail of the queue. This is why it can also be used for LIFO systems.

We’ll only briefly deal with the different types of queues since this is the collection that’s typically least used in the wild.

Queue implementations

The Queue interface extends the Collection interface. There are several implementations, with some of the most common ones being PriorityQueue, LinkedList, and ArrayDeque. The Deque interface, which extends the Queue interface, adds support for double-ended queues, allowing the insertion and removal of elements from both ends of the queue...