ConcurrentLinkedQueue Code Explanation

Question

http://www.java2s.com/Open-Source/Java-Open-Source-Library/7-JDK/java/java/util/concurrent/ConcurrentLinkedQueue.java.htm

The above is the source code of ConcurrentL

Answer 1

The ConcurrentLinkedQueue allows concurrent modification of the internal list while traversing it. This implies that the node you are looking at could have been removed concurrently. To detect such situations the next pointer of a removed node is changed to point to itself. Look at updateHead (L302) for details.