ArrayDeque
ArrayDeque is a resizable-array implementation of the Deque interface in Java, part of the java.util package. It provides a double-ended queue that supports efficient insertion and removal of elements at both ends, with constant-time performance for most operations. It is not thread-safe but is generally faster than Stack when used as a stack and faster than LinkedList when used as a queue.
Developers should use ArrayDeque when they need a high-performance, non-thread-safe collection for scenarios like implementing stacks, queues, or deques in Java applications, such as in algorithms requiring LIFO or FIFO operations, or for managing task buffers. It is particularly useful in performance-critical code where low overhead and fast access times are essential, as it avoids the synchronization costs of older classes like Vector or Stack.