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# Concurrent collections

* [Java Concurrent Utilities - JCU](#java-concurrent-utilities---jcu)
  * [List](#list)
  * [Map](#map)
  * [Set](#set)
  * [Queue](#queue)

## Java Concurrent Utilities - JCU

### List

* CopyOnWriteArrayList: It will have two lists inside. Each time a write operation happens, a new copied list will be created for write operations. Read operations will be performed on the original list

### Map

* ConcurrentHashMap: key not ordered
* ConcurrentSkiplistMap: key ordered

### Set

* CopyOnWriteArraySet
* ConcurrentSkipListSet

### Queue

**Single end queue**

* Blocking queue:
  * ArrayBlockingQueue: array as inside queue
  * LinkedBlockingQueue: list as inside queue
  * SynchronousQueue: No queue inside
  * LinkedTransferQueue: combination of synchronousQueue and LinkedBlockingQueue
* PriorityBlockingQueue
* DelayQueue

**Deque**

* BlockingDeque
* ConcurrentLinkedQueue
* ConcurrentLinkedDeque