code: public void addFile(String zipEntry, InputStream input) throws IOException {
  		if(input != null) {
  			stream.putNextEntry(new ZipEntry(zipEntry));
  			Streams.copy(input, stream);
  		}
  	}
docs: Adds a file to the ZIP archive, given its content as an input stream.
  
  @param zipEntry
  name of the entry in the archive.
  @param input
  the stream from which data will be read to be added to the ZIP archive;
  the stream must be open and will not be closed once the operation is
  complete, so it is up to the caller to release it.