private void moveToNextBatch(Context context) throws IOException, InterruptedException {
      if (targetHasher.isBatchStarted()) {
        finishBatchAndCompareHashes(context);
      }
      targetHasher.startBatch(nextSourceKey);
      currentSourceHash = sourceHashReader.getCurrentHash();

      findNextKeyHashPair();
    }
If there is an open hash batch, complete it and sync if there are diffs. Start a new batch,
and seek to read the
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/SyncTable.java