code: public void addFile(String zipEntry, File file) throws IOException {
  		String zipEntryName = Strings.isValid(zipEntry) ? zipEntry : file.getName();
  		logger.debug("adding '{}' as '{}'", file.getName(), zipEntryName);
  		try(InputStream input = new FileInputStream(file)) {
  			addFile(zipEntryName, input);
  		}
  	}
docs: Adds a file to a ZIP archive.
  
  @param zipEntry
  the name of entry in the archive; if null, the name of the original
  file is used.
  @param file
  File object representing the file to be added to the archive.