public static GIITestHook getGIITestHookForCheckingPurpose(final GIITestHookType type) {
    switch (type) {
      case BeforeGetInitialImage: // 0
        return internalBeforeGetInitialImage;
      case BeforeRequestRVV: // 1
        return internalBeforeRequestRVV;
      case AfterRequestRVV: // 2
        return internalAfterRequestRVV;
      case AfterCalculatedUnfinishedOps: // 3
        return internalAfterCalculatedUnfinishedOps;
      case BeforeSavedReceivedRVV: // 4
        return internalBeforeSavedReceivedRVV;
      case AfterSavedReceivedRVV: // 5
        return internalAfterSavedReceivedRVV;
      case AfterSentRequestImage: // 6
        return internalAfterSentRequestImage;

      case AfterReceivedRequestImage: // 7
        return internalAfterReceivedRequestImage;
      case DuringPackingImage: // 8
        return internalDuringPackingImage;
      case AfterSentImageReply: // 9
        return internalAfterSentImageReply;

      case AfterReceivedImageReply: // 10
        return internalAfterReceivedImageReply;
      case DuringApplyDelta: // 11
        return internalDuringApplyDelta;
      case BeforeCleanExpiredTombstones: // 12
        return internalBeforeCleanExpiredTombstones;
      case AfterSavedRVVEnd: // 13
        return internalAfterSavedRVVEnd;
      default:
        throw new RuntimeException("Illegal test hook type");
    }
  }
Helper method to register the filters.
geode-core/src/main/java/org/apache/geode/internal/cache/InitialImageOperation.java