@Override
    public void onDataCreate(String path) {
      if (!operationType.equals(StoreOperationType.CREATE) && !operationType.equals(StoreOperationType.WRITE)) {
        exceptionRef.set(new Exception("Data is created but wrong operation type is specified. " + operationType));
      }
      latch.countDown();
    }
Constructor.
@param latch The {@link CountDownLatch} to count down once the operation of specified type is done.
@param operationType The type of the operation to listen.
ambry-clustermap/src/test/java/com/github/ambry/clustermap/HelixStoreOperator.java