@Override public DruidWritable getCurrentValue() throws IOException, InterruptedException {
    // Create new value
    DruidWritable value = new DruidWritable(false);
    // 1) The timestamp column
    value.getValue().put(DruidConstants.EVENT_TIMESTAMP_COLUMN,
        currentRow.getTimestamp() == null ? null : currentRow.getTimestamp().getMillis()
    );
    // 2) The dimension columns
    value.getValue().putAll(currentEvent);
    return value;
  }
Record reader for results for Druid GroupByQuery.
druid-handler/src/java/org/apache/hadoop/hive/druid/serde/DruidGroupByQueryRecordReader.java