How to use

splitRangeByTablets

method

in

org.apache.accumulo.core.client.admin.TableOperations

private Collection<Range> splitByTabletBoundaries(String tableName, Collection<Range> ranges)
    throws org.apache.accumulo.core.client.TableNotFoundException, AccumuloException, AccumuloSecurityException
{
  ImmutableSet.Builder<Range> rangeBuilder = ImmutableSet.builder();
  for (Range range : ranges) {
    // if start and end key are equivalent, no need to split the range
    if (range.getStartKey() != null && range.getEndKey() != null && range.getStartKey().equals(range.getEndKey())) {
      rangeBuilder.add(range);
    }
    else {
      // Call out to Accumulo to split the range on tablets
      rangeBuilder.addAll(connector.tableOperations().splitRangeByTablets(tableName, range, Integer.MAX_VALUE));
    }
  }
  return rangeBuilder.build();
}

/**
 * Loads the cardinality for the given Range. Uses a BatchScanner and sums the cardinality for all values that encapsulate the Range.
 *
 * @param key Range to get the cardinality for
 * @return The cardinality of the column, which would be zero if the value does not exist
 */
@Override
public Long load(CacheKey key)
    throws Exception
{
  LOG.debug("Loading a non-exact range from Accumulo: %s", key);
  // Get metrics table name and the column family for the scanner
  String metricsTable = getMetricsTableName(key.getSchema(), key.getTable());
  Text columnFamily = new Text(getIndexColumnFamily(key.getFamily().getBytes(UTF_8), key.getQualifier().getBytes(UTF_8)).array());
  // Create scanner for querying the range
  BatchScanner scanner = connector.createBatchScanner(metricsTable, key.auths, 10);
  scanner.setRanges(connector.tableOperations().splitRangeByTablets(metricsTable, key.range, Integer.MAX_VALUE));
  scanner.fetchColumn(columnFamily, CARDINALITY_CQ_AS_TEXT);
  try {
    return stream(scanner)
        .map(Entry::getValue)
        .map(Value::toString)
        .mapToLong(Long::parseLong)
        .sum();
  }
  finally {
    scanner.close();
  }
}

@Override
public Set<org.apache.accumulo.proxy.thrift.Range> splitRangeByTablets(ByteBuffer login,
  String tableName, org.apache.accumulo.proxy.thrift.Range range, int maxSplits)
  throws org.apache.accumulo.proxy.thrift.AccumuloException,
  org.apache.accumulo.proxy.thrift.AccumuloSecurityException,
  org.apache.accumulo.proxy.thrift.TableNotFoundException, TException {
 try {
  Set<Range> ranges = getConnector(login).tableOperations().splitRangeByTablets(tableName,
    getRange(range), maxSplits);
  Set<org.apache.accumulo.proxy.thrift.Range> result = new HashSet<>();
  for (Range r : ranges) {
   result.add(getRange(r));
  }
  return result;
 } catch (Exception e) {
  handleExceptionTNF(e);
  return null;
 }
}

  .splitRangeByTablets(clientOpts.getTableName(), new Range(), opts.maxMaps);
AccumuloInputFormat.setRanges(job, ranges);
AccumuloInputFormat.setAutoAdjustRanges(job, false);

 conn.tableOperations().clone(opts.getTableName(), clone, true, new HashMap<String,String>(),
   new HashSet<String>());
 ranges = conn.tableOperations().splitRangeByTablets(opts.getTableName(), new Range(),
   opts.maxMaps);
 conn.tableOperations().offline(clone);
 AccumuloInputFormat.setOfflineTableScan(job, true);
} else {
 ranges = opts.getConnector().tableOperations().splitRangeByTablets(opts.getTableName(),
   new Range(), opts.maxMaps);

 break;
case 10:
 ops.splitRangeByTablets(tableName, new Range(), 10);
 fail();
 break;