code: private String getArchiveFileName(String archive) {
          String fileExtension = getFilenameExtension();
  
          if (archive.endsWith(fileExtension)) {
              return archive;
          } else if (archive.endsWith(archiver.getFilenameExtension())) {
              return archive + compressor.getFilenameExtension();
          } else {
              return archive + fileExtension;
          }
      }
docs: Returns a file name from the given archive name. The file extension suffix will be appended according to what is
  already present.
  <br>
  E.g. if the compressor uses the file extension "gz", the archiver "tar", and passed argument is "archive.tar",
  the returned value will be "archive.tar.gz".
  
  @param archive the existing archive file name
  @return the normalized archive file name including the correct file name extension