code: public void generate(final File fileName) {
          final File outputFile = removeTemplatePrefix(fileName);
          templateFile = fileName;
  
          try (final InputStream in = new BufferedInputStream(new FileInputStream(fileName));
               final OutputStream out = new BufferedOutputStream(new FileOutputStream(outputFile))) {
              final Transformer transformer = TransformerFactory.newInstance().newTransformer();
              final SAXParserFactory parserFactory = SAXParserFactory.newInstance();
              parserFactory.setNamespaceAware(true);
              XMLReader reader = parserFactory.newSAXParser().getXMLReader();
              this.setContentHandler(null);
              this.setParent(reader);
              reader = this;
              final Source source = new SAXSource(reader, new InputSource(in));
              source.setSystemId(fileName.toURI().toString());
              final Result result = new StreamResult(out);
              transformer.transform(source, result);
          } catch (final RuntimeException e) {
              throw e;
          } catch (final Exception e) {
              logger.error("Failed to transform " + fileName + ": " + e.getMessage(), e);
          }
      }
docs: Generator the output file.
  @param fileName filename