Collections: Collections.fill overwrites every slot with one value

Collections.fill replaces every element of a list with the same value in place, which is a quick way to reset a fixed-size list without recreating it.

Code

List<String> slots = new ArrayList<>(List.of("a", "b", "c", "d"));
Collections.fill(slots, "empty");
System.out.println("Filled: " + slots);

Output

Filled: [empty, empty, empty, empty]