logger.info("SuggestCreator is stopped.");
            }
            exitCode = Constants.EXIT_FAIL;
        } catch (final Throwable t) {
            logger.error("SuggestCreator terminated unexpectedly.", t);
            exitCode = Constants.EXIT_FAIL;
        } finally {
            if (systemMonitorTask != null) {
                systemMonitorTask.cancel();
            }

    // Read the command.
    val version = fromSource.readByte() and 0xff
    if (version != VERSION_5) throw ProtocolException("unexpected version: $version")

    val command = fromSource.readByte() and 0xff

    val reserved = fromSource.readByte() and 0xff
    if (reserved != 0) throw ProtocolException("unexpected reserved: $reserved")

    val addressType = fromSource.readByte() and 0xff
    val toAddress =

  // here to provide error messages.
  // TODO(user): Some Strings used in the subclasses can be added as static Strings
  // here too.
  static final String ERROR_MODIFIABLE_SET = "Set returned is unexpectedly modifiable";
  static final String ERROR_SELF_LOOP = "self-loops are not allowed";
  static final String ERROR_ADDED_SELF_LOOP = "Should not be allowed to add a self-loop edge.";

     *
     * - _can_ be null without causing a runtime failure (because we don't want the interesting
     *   details of precondition failure to be hidden by an exception we throw about an unexpectedly
     *   null _failure message_)
     *
     * That combination upsets NullPointerTester, which wants any call that passes null for a
     * non-@Nullable parameter to trigger a NullPointerException.
     *

     *
     * - _can_ be null without causing a runtime failure (because we don't want the interesting
     *   details of precondition failure to be hidden by an exception we throw about an unexpectedly
     *   null _failure message_)
     *
     * That combination upsets NullPointerTester, which wants any call that passes null for a
     * non-@Nullable parameter to trigger a NullPointerException.
     *

                logger.info("Crawler is stopped.");
            }
            exitCode = Constants.EXIT_FAIL;
        } catch (final Throwable t) {
            logger.error("Crawler terminated unexpectedly.", t);
            exitCode = Constants.EXIT_FAIL;
        } finally {
            if (commandThread != null && commandThread.isAlive()) {
                commandThread.interrupt();
            }

            service,
            from);
        checkState(
            servicesByState.put(to, service),
            "Service %s in the state map unexpectedly at %s",
            service,
            to);
        // Update the timer
        Stopwatch stopwatch = startupTimers.get(service);
        if (stopwatch == null) {

    if (alreadyStartedAddress != null) {
      check(socketAddress.address == alreadyStartedAddress.address) {
        "unexpected address"
      }
      check(socketAddress.port == 0 || socketAddress.port == alreadyStartedAddress.port) {
        "unexpected port"
      }
      return // Already started.
    }

    var boundSocketAddress = socketAddress
    try {

		}

		obj, err := x.getIdx(i)
		if err != nil {
			return nil, err
		}
		switch ver.header.Type {
		case ObjectType:
			if obj.ObjectV2 == nil {
				return nil, errors.New("obj.ObjectV2 unexpectedly nil")
			}
			dds = append(dds, uuid.UUID(obj.ObjectV2.DataDir).String())
			if obj.ObjectV2.VersionID == [16]byte{} {
				dds = append(dds, nullVersionID)
			} else {

			t.Errorf("test %d, canary byte unexpectedly consumed", i)
		}
	}
}

// testNonEmptyReader wraps an io.Reader and ensures that
// Read is never called with an empty buffer.
type testNonEmptyReader struct{ io.Reader }

func (r testNonEmptyReader) Read(b []byte) (int, error) {
	if len(b) == 0 {
		return 0, errors.New("unexpected empty Read call")
	}
	return r.Reader.Read(b)
}