* without it because it is an immutable object in a volatile field. This is desirable so that
   * methods like {@link #state}, {@link #failureCause} and notably {@link #toString} can be run
   * without grabbing the lock.
   *
   * <p>To update this field correctly the lock must be held to guarantee that the state is
   * consistent.
   */
  private volatile StateSnapshot snapshot = new StateSnapshot(NEW);

        super();
    }

    /**
     * A map containing query information for KeyMatch.
     * The key is a virtual host, and the value is a map of terms and boost information.
     */
    protected volatile Map<String, Map<String, List<Tuple3<String, QueryBuilder, ScoreFunctionBuilder<?>>>>> keyMatchQueryMap =
            Collections.emptyMap();

    /**
     * Initializes the helper.

  }

  private static final class NoOpScheduledExecutorService extends AbstractListeningExecutorService
      implements ListeningScheduledExecutorService {

    private volatile boolean shutdown;

    @Override
    public void shutdown() {
      shutdown = true;
    }

    @Override
    public List<Runnable> shutdownNow() {
      shutdown();

    /** Map of path mappings by process type. */
    protected final Map<String, List<PathMapping>> pathMappingMap = new HashMap<>();

    /** Cached list of path mappings. */
    protected volatile List<PathMapping> cachedPathMappingList = null;

    /**
     * Initializes the path mapping helper.
     */
    @PostConstruct
    public void init() {
        if (logger.isDebugEnabled()) {

    // A handle to the running task so that we can stop it when a shutdown has been requested.
    // These two fields are volatile because their values will be accessed from multiple threads.
    private volatile @Nullable Cancellable runningTask;
    private volatile @Nullable ScheduledExecutorService executorService;

    // This lock protects the task so we can ensure that none of the template methods (startUp,

 *
 * @author Justin T. Sampson
 */
@NullUnmarked
public abstract class MonitorTestCase extends TestCase {

  public class TestGuard extends Monitor.Guard {
    private volatile boolean satisfied;

    public TestGuard(boolean satisfied) {
      super(MonitorTestCase.this.monitor);
      this.satisfied = satisfied;
    }

    @Override
    public boolean isSatisfied() {

    GcFinalization.awaitDone(() -> reference.finalizeReferentCalled);
  }

  static class MockReference extends FinalizableWeakReference<Object> {

    volatile boolean finalizeReferentCalled;

    MockReference(FinalizableReferenceQueue frq) {
      super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;

    GcFinalization.awaitDone(() -> reference.finalizeReferentCalled);
  }

  static class MockReference extends FinalizableWeakReference<Object> {

    volatile boolean finalizeReferentCalled;

    MockReference(FinalizableReferenceQueue frq) {
      super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;

        .testAllPublicInstanceMethods(manager);
  }

  private static final class RecordingListener extends ServiceManager.Listener {
    volatile boolean healthyCalled;
    volatile boolean stoppedCalled;
    final Set<Service> failedServices = Sets.newConcurrentHashSet();

    @Override
    public void healthy() {
      healthyCalled = true;
    }

    @Override

    }

    /** Atomic counter for the number of documents processed */
    protected AtomicLong documentSize = new AtomicLong(0);

    /** Total execution time for all operations */
    protected volatile long executeTime = 0;

    /** List of documents waiting to be indexed */
    protected final DocList docList = new DocList();

    /** Maximum size of document requests in bytes */