@GwtIncompatible
@ElementTypesAreNonnullByDefault
public class UncheckedTimeoutException extends RuntimeException {
  public UncheckedTimeoutException() {}

  public UncheckedTimeoutException(@CheckForNull String message) {
    super(message);
  }

  public UncheckedTimeoutException(@CheckForNull Throwable cause) {
    super(cause);
  }

  public UncheckedTimeoutException(@CheckForNull String message, @CheckForNull Throwable cause) {

    SampleImpl target = new SampleImpl(9999);
    Sample proxy = service.newProxy(target, Sample.class, NOT_ENOUGH_MS, MILLISECONDS);
    Stopwatch stopwatch = Stopwatch.createStarted();

    assertThrows(UncheckedTimeoutException.class, () -> proxy.sleepThenReturnInput("x"));

    assertThat(stopwatch.elapsed(MILLISECONDS)).isIn(Range.closed(NOT_ENOUGH_MS, DELAY_MS * 2));
    // Is it still computing away anyway?

    SampleImpl target = new SampleImpl(9999);
    Sample proxy = service.newProxy(target, Sample.class, NOT_ENOUGH_MS, MILLISECONDS);
    Stopwatch stopwatch = Stopwatch.createStarted();

    assertThrows(UncheckedTimeoutException.class, () -> proxy.sleepThenReturnInput("x"));

    assertThat(stopwatch.elapsed(MILLISECONDS)).isIn(Range.closed(NOT_ENOUGH_MS, DELAY_MS * 2));
    // Is it still computing away anyway?

   * exception is propagated to the caller exactly as-is. If, on the other hand, the time limit is
   * reached, the proxy will attempt to abort the call to the target, and will throw an {@link
   * UncheckedTimeoutException} to the caller.
   *
   * <p>It is important to note that the primary purpose of the proxy object is to return control to
   * the caller when the timeout elapses; aborting the target method call is of secondary concern.

      throw e;
    } catch (ExecutionException e) {
      throw throwCause(e, true /* combineStackTraces */);
    } catch (TimeoutException e) {
      future.cancel(true);
      throw new UncheckedTimeoutException(e);
    }
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public <T extends @Nullable Object> T callWithTimeout(