Method remove

output/java_guava/1.4.17/AtomicLongMap.java:256–272

Removes and returns the value associated with key. If key is not in the map, this method has no effect and returns zero.

(K key)

   */

  @CanIgnoreReturnValue
  public long remove(K key) {
    AtomicLong atomic = map.get(key);
    if (atomic == null) {
      return 0L;
    }

    while (true) {
      long oldValue = atomic.get();
      if (oldValue == 0L || atomic.compareAndSet(oldValue, 0L)) {
        // only remove after setting to zero, to avoid concurrent updates
        map.remove(key, atomic);
        // succeed even if the remove fails, since the value was already adjusted
        return oldValue;
      }
    }
  }

  /**
   * Removes all mappings from this map whose values are zero.