ArrayDeque vs ArrayList to implement a stack

The main difference between both implementation is the resize strategy

• ArrayList is resized to a new size of oldCapacity + (oldCapacity >> 1), resulting in an increse of ~50%. The default capacity is 10, resulting in a capacities after resize of 15, 22, 33, 49, 73, 109, 163, 244, 366…

• ArrayDeque is always resized to a power of 2. On resize, the capacity is doubled. Starting with the default of 16, the resuling capacities after resize are 32, 64, 128, 256,…

So the ArrayDeque reaches higher capacities with much less resize operation, which are costly because of array copy. I.e. to store 256 in default-sized ArrayList, it requires 9 resize calls, while the ArrayDeque only need 4.
Array copy may be fast, but may also require a GC to free some space for the new data sets, in addition to the memory copy costs (where the ArrayDeque might also perform better due to it’s alignment to power-of-2).

Both datastructures have best-case complexity of O(1) for push and pop through direct access on either head & tail (ArrayDequeue) respectively add and remove(Last) size (ArrayList)