Java Collections (LIFO Structure)

Question

I am looking in the Collections framework of Java for a LIFO Structure (Stack) without any success. Basically I want a really simple stack; my perfect option would be a Dequ

Answer 1

Deque & LinkedList

Just for the sake of completeness I'm providing an example using Deque interface and a LinkedList implementation.

    Deque deque = new LinkedList<>();
    deque.add("first");
    deque.add("last");

    // returns "last" without removing it
    System.out.println(deque.peekLast());

    // removes and returns "last"
    System.out.println(deque.pollLast());

Backing up a Deque by a LinkedList is great for performance, since inserting and removing elements from it is done in constant time (O(1)).

Using a LinkedList alone:

    LinkedList list = new LinkedList<>();
    list.add("first");
    list.add("last");

    // returns "last" without removing it
    System.out.println(list.getLast());

    // removes and returns "last"
    System.out.println(list.removeLast());