@Override
    public List<Pair<NonceKey, WALEdit>>
      buildWALEdits(final MiniBatchOperationInProgress<Mutation> miniBatchOp) throws IOException {
      List<Pair<NonceKey, WALEdit>> walEdits = super.buildWALEdits(miniBatchOp);
      // for MutationBatchOperation, more than one nonce is not allowed
      if (walEdits.size() > 1) {
        throw new IOException("Found multiple nonce keys per batch!");
      }
      return walEdits;
    }
Returns Get the long out of the passed in Cell
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java