Runtime

SetaddremovecontainsnextsizeData Structure
HashSetO(1)O(1)O(1)O(h/n)O(1)Hash Table
LinkedHashSetO(1)O(1)O(1)O(1)O(1)Hash Table + Linked List
EnumSetO(1)O(1)O(1)O(1)O(1)Bit Vector
TreeSetO(log n)O(log n)O(log n)O(log n)O(1)Red-black tree
CopyOnWriteArraySetO(n)O(n)O(n)O(1)O(1)Array
ConcurrentSkipListSetO(log n)O(log n)O(log n)O(1)O(n)Skip List