code: @Override
    public void addEntry(Archivable arch) throws IOException {
      final String fn = arch.getFileName();
      TarArchiveEntry entry = new TarArchiveEntry(fn);
      byte[] cbytes = arch.getBytes();
      entry.setSize(cbytes.length);
      this.tos.putArchiveEntry(entry);
      try (ByteArrayInputStream bis = new ByteArrayInputStream(cbytes)) {
        IOUtils.copy(bis, tos);
        tos.closeArchiveEntry();
      }
    }
docs: /*
  (non-Javadoc)
  @see edu.jhu.hlt.acute.archivers.Archiver#addEntry(edu.jhu.hlt.acute.archivers.Archivable)