code: public static List<File> map(File workDir, File inputFile, Mapper mapper, String prefix)
              throws DataUtilException {
          List<File> files = new ArrayList<File>();
          files.add(inputFile);
          return map(workDir, files, mapper, prefix);
      }
docs: This method functions provide map (map-reduce) like functionality. For every row in the input data there is a
  call to the mapper callback method;
  @param workDir work directory where the mapped files will be created
  @param inputFile input file
  @param mapper callback method, a class that implements the Mappable interface
  @param prefix prefix name for the output file
  @throws DataUtilException data util exception