/*
         * We can't inherit the normal implementation (which calls
         * Sets.removeAllImpl(Set, *Collection*)) because, under some
         * circumstances, it attempts to call columnKeySet().iterator().remove,
         * which is unsupported.
         */
        checkNotNull(c);
        return Sets.removeAllImpl(this, c.iterator());
      }

      @Override

   *
   * <p>The returned {@code Future} attempts to keep its cancellation state in sync with that of the
   * input future and that of the future returned by the chain function. That is, if the returned
   * {@code Future} is cancelled, it will attempt to cancel the other two, and if either of the
   * other two is cancelled, the returned {@code Future} will receive a callback in which it will
   * attempt to cancel itself.
   *

  }

  private fun runWriter() {
    assertLockHeld()

    val writerTask = writerTask
    if (writerTask != null) {
      taskQueue.schedule(writerTask)
    }
  }

  /**
   * Attempts to remove a single frame from a queue and send it. This prefers to write urgent pongs
   * before less urgent messages and close frames. For example, it's possible that a caller will

        /*
         * We can't inherit the normal implementation (which calls
         * Sets.removeAllImpl(Set, *Collection*)) because, under some
         * circumstances, it attempts to call columnKeySet().iterator().remove,
         * which is unsupported.
         */
        checkNotNull(c);
        return Sets.removeAllImpl(this, c.iterator());
      }

      @Override

 * }
 *
 * <p>changes the entries iteration order to {@code [key2=bar, key1=baz]} and the key iteration
 * order to {@code [key2, key1]}. The {@link #entries()} iterator returns mutable map entries, and
 * {@link #replaceValues} attempts to preserve iteration order as much as possible.
 *
 * <p>The collections returned by {@link #keySet()} and {@link #asMap()} iterate through the keys in

 *  Fix: Don't crash in SPDY and HTTP/2 when disconnecting before connecting.
 *  Fix: Avoid a reverse DNS-lookup for a numeric proxy address
 *  Fix: Resurrect http/2 frame logging.
 *  Fix: Limit to 20 authorization attempts.

## Version 2.1.0

_2014-11-11_

 *  New: Typesafe APIs for interacting with cipher suites and TLS versions.
 *  Fix: Don't crash when mixing authorization challenges with upload retries.

        : copyOf(elements.iterator());
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *

    protected boolean usePersistentHandles = false;
    /** Timeout for durable handles in milliseconds */
    protected long durableHandleTimeout = 120000; // 2 minutes
    /** Maximum number of retry attempts for handle reconnection */
    protected int handleReconnectRetries = 3;
    /** Directory to store persistent handle state */
    protected String handleStateDirectory;

    // Directory leasing configuration fields

     */
    long getDurableHandleTimeout();

    /**
     * Property {@code jcifs.smb.client.handleReconnectRetries}, defaults to 3
     *
     * @return maximum number of retry attempts for handle reconnection
     */
    int getHandleReconnectRetries();

    /**
     * Enable SMB3 Multi-Channel support
     *
     * Property {@code jcifs.smb.client.useMultiChannel} (boolean, default true)

          helper = new SynchronizedHelper();
        }
      }
    } else {
      /*
       * We avoid Unsafe, since newer JVMs produce warnings or even errors for attempts to use it.
       *
       * In guava-jre, we avoid Unsafe by using VarHandle instead. But if we have references to
       * VarHandle in guava-android, even if they're unused under Android, we cause errors under