return sizeIfKnown.get() == 0L;
    }
    Closer closer = Closer.create();
    try {
      InputStream in = closer.register(openStream());
      return in.read() == -1;
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

  /**
   * Returns the size of this source in bytes, if the size can be easily determined without actually

        // to currentFuture doesn't race with itself so that currentFuture is assigned in the
        // correct order.
        Throwable scheduleFailure = null;
        Cancellable toReturn;
        lock.lock();
        try {
          toReturn = initializeOrUpdateCancellationDelegate(schedule);
        } catch (Throwable e) {
          // Any Exception is either a RuntimeException or sneaky checked exception.
          //

      return lengthIfKnown.get();
    }

    Closer closer = Closer.create();
    try {
      Reader reader = closer.register(openStream());
      return countBySkipping(reader);
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

  private long countBySkipping(Reader reader) throws IOException {
    long count = 0;
    long read;

      return lengthIfKnown.get();
    }

    Closer closer = Closer.create();
    try {
      Reader reader = closer.register(openStream());
      return countBySkipping(reader);
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

  private long countBySkipping(Reader reader) throws IOException {
    long count = 0;
    long read;

    }

    @Override
    public OptionalThing<ApiResponse> handleServerException(final ApiFailureResource resource, final Throwable cause) {
        return OptionalThing.of(asJson(createFailureBean(Status.SYSTEM_ERROR, createMessage(resource, cause))));
    }

    // ===================================================================================

    address: InetSocketAddress,
    connectTimeout: Int,
  ) {
    socket.connect(address, connectTimeout)
  }

  open fun log(
    message: String,
    level: Int = INFO,
    t: Throwable? = null,
  ) {
    val logLevel = if (level == WARN) Level.WARNING else Level.INFO
    logger.log(logLevel, message, t)
  }

  open fun isCleartextTrafficPermitted(hostname: String): Boolean = true

  /**

  public void testForwardExceptionFastPath() throws Exception {
    class FailFuture extends InternalFutureFailureAccess implements ListenableFuture<String> {
      final Throwable failure;

      FailFuture(Throwable throwable) {
        failure = throwable;
      }

      @Override
      public boolean cancel(boolean mayInterruptIfRunning) {

      this.runtime = runtime;
    }

    @Override
    public void uncaughtException(Thread t, Throwable e) {
      try {
        logger
            .get()
            .log(
                SEVERE,
                String.format(Locale.ROOT, "Caught an exception in %s.  Shutting down.", t),
                e);
      } catch (Throwable errorInLogging) { // sneaky checked exception

   * so tests pass on GraalVM, where suppressed exceptions are silently discarded.
   *
   * https://github.com/oracle/graal/issues/3008
   */
  @JvmStatic
  fun Throwable.assertSuppressed(block: (List<@JvmSuppressWildcards Throwable>) -> Unit) {
    if (isGraalVmImage) return
    block(suppressed.toList())
  }

  @JvmStatic
  fun threadFactory(name: String): ThreadFactory =
    object : ThreadFactory {

    }

    /**
     * Builds a comprehensive error message from a throwable and its causes.
     * This method traverses the cause chain and concatenates all error messages.
     *
     * @param t the throwable to build message from
     * @return a string containing all error messages in the cause chain
     */
    protected String buildThrowableMessage(final Throwable t) {
        final StringBuilder buf = new StringBuilder(100);