@Override
 public int getOrCreate(
     AbstractTransactionManager txManager,
     EntityIdGenerator idGenerator,
     PersistenceManager persistence,
     String name) {
   Response<Integer> response =
       master.createPropertyKey(requestContextFactory.newRequestContext(), name);
   xaDsm.applyTransactions(response);
   return response.response().intValue();
 }
  private void checkDataConsistencyWithMaster(
      URI availableMasterId,
      Master master,
      NeoStoreXaDataSource nioneoDataSource,
      TransactionIdStore transactionIdStore)
      throws IOException {
    long myLastCommittedTx = transactionIdStore.getLastCommittingTransactionId();

    int myMaster = -1;
    long myChecksum = 0;
    TransactionMetadataCache.TransactionMetadata metadata =
        nioneoDataSource
            .getDependencyResolver()
            .resolveDependency(LogicalTransactionStore.class)
            .getMetadataFor(myLastCommittedTx);

    myMaster = metadata.getMasterId();
    myChecksum = metadata.getChecksum();

    HandshakeResult handshake;
    try (Response<HandshakeResult> response =
        master.handshake(myLastCommittedTx, nioneoDataSource.getStoreId())) {
      handshake = response.response();
      requestContextFactory.setEpoch(handshake.epoch());
    } catch (BranchedDataException e) {
      // Rethrow wrapped in a branched data exception on our side, to clarify where the problem
      // originates.
      throw new BranchedDataException(
          "The database stored on this machine has diverged from that "
              + "of the master. This will be automatically resolved.",
          e);
    } catch (RuntimeException e) {
      // Checked exceptions will be wrapped as the cause if this was a serialized
      // server-side exception
      if (e.getCause() instanceof MissingLogDataException) {
        /*
         * This means the master was unable to find a log entry for the txid we just asked. This
         * probably means the thing we asked for is too old or too new. Anyway, since it doesn't
         * have the tx it is better if we just throw our store away and ask for a new copy. Next
         * time around it shouldn't have to even pass from here.
         */
        throw new StoreOutOfDateException(
            "The master is missing the log required to complete the " + "consistency check",
            e.getCause());
      }
      throw e;
    }

    if (myMaster != -1
        && (myMaster != handshake.txAuthor() || myChecksum != handshake.txChecksum())) {
      String msg =
          "The cluster contains two logically different versions of the database.. This will be "
              + "automatically resolved. Details: I (machineId:"
              + config.get(ClusterSettings.server_id)
              + ") think machineId for txId ("
              + myLastCommittedTx
              + ") is "
              + myMaster
              + ", but master (machineId:"
              + getServerId(availableMasterId)
              + ") says that it's "
              + handshake;
      throw new BranchedDataException(msg);
    }
    msgLog.logMessage(
        "Master id for last committed tx ok with highestTxId="
            + myLastCommittedTx
            + " with masterId="
            + myMaster,
        true);
  }
  private void checkDataConsistency(
      RequestContextFactory requestContextFactory,
      NeoStoreXaDataSource nioneoDataSource,
      URI masterUri)
      throws Throwable {
    // Must be called under lock on XaDataSourceManager
    LifeSupport checkConsistencyLife = new LifeSupport();
    TransactionIdStore txIdStore = null;
    try {
      MasterClient checkConsistencyMaster =
          newMasterClient(masterUri, nioneoDataSource.getStoreId(), checkConsistencyLife);
      checkConsistencyLife.start();
      console.log("Checking store consistency with master");
      txIdStore =
          nioneoDataSource.getDependencyResolver().resolveDependency(TransactionIdStore.class);
      checkDataConsistencyWithMaster(
          masterUri, checkConsistencyMaster, nioneoDataSource, txIdStore);
      console.log("Store is consistent");

      /*
       * Pull updates, since the store seems happy and everything. No matter how far back we are, this is just
       * one thread doing the pulling, while the guard is up. This will prevent a race between all transactions
       * that may start the moment the database becomes available, where all of them will pull the same txs from
       * the master but eventually only one will get to apply them.
       */
      console.log("Catching up with master");

      resolver
          .resolveDependency(TransactionCommittingResponseUnpacker.class)
          .unpackResponse(
              checkConsistencyMaster.pullUpdates(requestContextFactory.newRequestContext()));
      console.log("Now consistent with master");
    } catch (NoSuchLogVersionException e) {
      msgLog.logMessage(
          "Cannot catch up to master by pulling updates, because I cannot find the archived "
              + "logical log file that has the transaction I would start from. I'm going to copy the whole "
              + "store from the master instead.");
      try {
        stopServicesAndHandleBranchedStore(config.get(HaSettings.branched_data_policy));
      } catch (Throwable throwable) {
        msgLog.warn("Failed preparing for copying the store from the master instance", throwable);
      }
      throw e;
    } catch (StoreUnableToParticipateInClusterException upe) {
      console.log(
          "The store is inconsistent. Will treat it as branched and fetch a new one from the master");
      msgLog.warn(
          "Current store is unable to participate in the cluster; fetching new store from master",
          upe);
      try {
        stopServicesAndHandleBranchedStore(config.get(HaSettings.branched_data_policy));
      } catch (IOException e) {
        msgLog.warn("Failed while trying to handle branched data", e);
      }

      throw upe;
    } catch (MismatchingStoreIdException e) {
      console.log(
          "The store does not represent the same database as master. Will remove and fetch a new one from master");
      if (txIdStore.getLastCommittingTransactionId() == 0) {
        msgLog.warn("Found and deleting empty store with mismatching store id " + e.getMessage());
        stopServicesAndHandleBranchedStore(BranchedDataPolicy.keep_none);
      } else {
        msgLog.error("Store cannot participate in cluster due to mismatching store IDs");
      }
      throw e;
    } finally {
      checkConsistencyLife.shutdown();
    }
  }