}

  @Override
  public void execute(Runnable command) {
    Preconditions.checkNotNull(command, "command must not be null!");
    delegate.execute(command);
  }

  @Override
  public ListenableScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
    Preconditions.checkNotNull(command, "command must not be null");
    Preconditions.checkNotNull(unit, "unit must not be null!");

    }

    @Override
    public ListenableScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
      return NeverScheduledFuture.create();
    }

    @Override
    public ListenableScheduledFuture<?> scheduleAtFixedRate(
        Runnable command, long initialDelay, long period, TimeUnit unit) {
      return NeverScheduledFuture.create();
    }

    @Override

    addCallback(f, callback, directExecutor());
  }

  private class CountingSameThreadExecutor implements Executor {
    int runCount = 0;

    @Override
    public void execute(Runnable command) {
      command.run();
      runCount++;
    }
  }

  private final class MockCallback implements FutureCallback<String> {
    @Nullable private String value = null;
    @Nullable private Throwable failure = null;

  }

  @Override
  public void execute(Runnable command) {
    Preconditions.checkNotNull(command, "command must not be null!");
    delegate.execute(command);
  }

  @Override
  public ListenableScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
    Preconditions.checkNotNull(command, "command must not be null");
    Preconditions.checkNotNull(unit, "unit must not be null!");

      Runnable command, long initialDelay, long period, TimeUnit unit) {
    return delegate.scheduleAtFixedRate(wrapTask(command), initialDelay, period, unit);
  }

  @Override
  public final ScheduledFuture<?> scheduleWithFixedDelay(
      Runnable command, long initialDelay, long delay, TimeUnit unit) {
    return delegate.scheduleWithFixedDelay(wrapTask(command), initialDelay, delay, unit);
  }

    @Override
    protected <T> Callable<T> wrapTask(Callable<T> callable) {
      return new WrappedCallable<T>(callable);
    }

    @Override
    protected Runnable wrapTask(Runnable command) {
      return new WrappedRunnable(command);
    }
  }

  private static final class MockExecutor implements ScheduledExecutorService {
    String lastMethodCalled = "";
    long lastInitialDelay;
    long lastDelay;

   * Wraps a {@code Runnable} for submission to the underlying executor. The default implementation
   * delegates to {@link #wrapTask(Callable)}.
   */
  protected Runnable wrapTask(Runnable command) {
    Callable<Object> wrapped = wrapTask(Executors.callable(command, null));
    return () -> {
      try {
        wrapped.call();
      } catch (Exception e) {
        restoreInterruptIfIsInterruptedException(e);
        throwIfUnchecked(e);

    for (int i = 0; i < 100; i++) {
      descending[i] = (byte) (99 - i);
    }
    assertCrc(0xd022db97, descending);
  }

  public void testScsiReadCommand() {
    // Test SCSI read command.
    byte[] scsiReadCommand =
        new byte[] {
          0x01, (byte) 0xc0, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00,

  public void testTimeout() throws Exception {
    // Create a service whose executor will never run its commands
    Service service =
        new TestService() {
          @Override
          protected Executor executor() {
            return new Executor() {
              @Override
              public void execute(Runnable command) {}
            };
          }

          @Override

  @Override
  ListenableScheduledFuture<?> scheduleAtFixedRate(
      Runnable command, long initialDelay, long period, TimeUnit unit);

  /** @since 15.0 (previously returned ScheduledFuture) */
  @Override
  ListenableScheduledFuture<?> scheduleWithFixedDelay(
      Runnable command, long initialDelay, long delay, TimeUnit unit);