public static HCatReader getHCatReader(final ReaderContext context,
                                         int slaveNumber) {
    // In future, this may examine config to return appropriate HCatReader
    return getHCatReader(context, slaveNumber, DefaultStateProvider.get());
  }
This should only be called once from every slave node to obtain an instance
of {@link HCatReader}.

@param context
         reader context obtained at the master node
@param slaveNumber
         which slave this is, determines which part of the read is done
@return {@link HCatReader}
hcatalog/core/src/main/java/org/apache/hive/hcatalog/data/transfer/DataTransferFactory.java