docs: protected Source createSource(final Resource resolvedResource, String base)
              throws TransformerException {
          final InputStream resourceStream;
          try {
              resourceStream = resolvedResource.getInputStream();
          } catch (IOException e) {
              throw new TransformerException("Failed to get InputStream for " + resolvedResource, e);
          }
  
          final StreamSource streamSource = new StreamSource(resourceStream);
          streamSource.setSystemId(base);
          return streamSource;
      }