code: public SyndFeed build(final InputSource is) throws IllegalArgumentException, FeedException {
          return new SyndFeedImpl(feedInput.build(is), preserveWireFeed);
      }
docs: Builds SyndFeedImpl from an W3C SAX InputSource.
  <p>
  
  @param is W3C SAX InputSource to read to create the SyndFeedImpl.
  @return the SyndFeedImpl read from the W3C SAX InputSource.
  @throws IllegalArgumentException thrown if feed type could not be understood by any of the
  underlying parsers.
  @throws FeedException if the feed could not be parsed