src/main/java/org/jboss/util/collection/ConcurrentSkipListMap.java
boolean casNext(Node<K,V> cmp, Node<K,V> val) {
            return nextUpdater.compareAndSet(this, cmp, val);
        }
boolean casNext(Node<K,V> cmp, Node<K,V> val) {
            return nextUpdater.compareAndSet(this, cmp, val);
        }
compareAndSet next field