code: public static InputStream runDOT(Reader r, String format, String... additionalOpts) throws IOException {
          String[] dotCommand = buildDOTCommand(format, additionalOpts);
  
          Process p = ProcessUtil.buildProcess(dotCommand, r, null, LOGGER::warn);
  
          return p.getInputStream();
      }
docs: Invokes the GraphVIZ DOT utility for rendering graphs.
  
  @param r
  the reader from which the GraphVIZ description is obtained.
  @param format
  the output format, as understood by the dot utility, e.g., png, ps, ...
  
  @return an input stream from which the image data can be read.
  
  @throws IOException
  if reading from the specified reader fails.