static final Object NULL = new Object();

  static final LazyLogger log = new LazyLogger(AbstractFuture.class);

  static final boolean GENERATE_CANCELLATION_CAUSES = false;

  private volatile @Nullable Object value;

  private volatile @Nullable Listener listeners;

    private final Settings settings;

    private final boolean expand;

    private long reloadInterval = 0;

    private final Environment env;

    private volatile long lastModified;

    private volatile long lastChecked;

    private volatile SynonymMap synonymMap;

    public SynonymLoader(final Environment env, final Settings settings, final boolean expand, final Analyzer analyzer) {
        this.env = env;

    protected volatile Map<String, Map<String, AccessResultImpl<Long>>> sessionMap = new HashMap<>();

    /** Map of session IDs to include URL patterns for filtering URLs. */
    protected volatile Map<String, List<Pattern>> includeUrlPatternMap = new HashMap<>();

    /** Map of session IDs to exclude URL patterns for filtering URLs. */

   *
   * Note about volatile: volatile doesn't make it safe to read from a mutable graph in one thread
   * while writing to it in another. All it does is help with _reading_ from multiple threads
   * concurrently. For more information, see AbstractNetworkTest.concurrentIteration.
   */
  private transient volatile @Nullable Entry<K, V> cacheEntry;

  MapIteratorCache(Map<K, V> backingMap) {

        /** RDMA write operation */
        WRITE
    }

    private final long requestId;
    private final RequestType type;
    private final RdmaMemoryRegion memoryRegion;
    private volatile boolean completed;
    private volatile Exception error;

    /**
     * Create new RDMA work request
     *
     * @param requestId unique request identifier
     * @param type type of request

    /** Register for IP address change notifications */
    public static final int WITNESS_REGISTER_IP_NOTIFICATION = 0x00000001;

    // Registration state
    private volatile WitnessRegistrationState state;
    private volatile long lastHeartbeat;
    private volatile int heartbeatFailures;
    private int flags;

    /**
     * Enumeration of possible witness registration states.
     */
    public enum WitnessRegistrationState {

 *
 * @author James Sexton
 */
final class MapRetrievalCache<K, V> extends MapIteratorCache<K, V> {
  // See the note about volatile in the superclass.
  private transient volatile @Nullable CacheEntry<K, V> cacheEntry1;
  private transient volatile @Nullable CacheEntry<K, V> cacheEntry2;

  MapRetrievalCache(Map<K, V> backingMap) {
    super(backingMap);
  }

  Callback {
  constructor(call: Call, listener: EventSourceListener) : this(call, call.request(), listener)

  constructor(response: Response, listener: EventSourceListener) : this(null, response.request, listener)

  @Volatile private var canceled = false

  override fun onResponse(
    call: Call,
    response: Response,
  ) {
    processResponse(response)
  }

  internal fun processResponse(response: Response) {

  private val http2Connection: Http2Connection,
) : ExchangeCodec {
  @Volatile private var stream: Http2Stream? = null

  private val protocol: Protocol =
    if (Protocol.H2_PRIOR_KNOWLEDGE in client.protocols) {
      Protocol.H2_PRIOR_KNOWLEDGE
    } else {
      Protocol.HTTP_2
    }

  @Volatile
  private var canceled = false

  override val isResponseComplete: Boolean

   * triggered by cancel(). For details, see the comments on the fields of TimeoutFuture.
   *
   * <p>{@code volatile} is required for j2objc transpiling:
   * https://developers.google.com/j2objc/guides/j2objc-memory-model#atomicity
   */
  private volatile @Nullable InterruptibleTask<?> task;

  TrustedListenableFutureTask(Callable<V> callable) {
    this.task = new TrustedFutureInterruptibleTask(callable);