code: public static SyndFeed combineFeeds(final SyndFeed originalFeed, final SyndFeed newFeed) {
          try {
              final SyndFeed result = (SyndFeed) newFeed.clone();
              result.getEntries().addAll(result.getEntries().size(), originalFeed.getEntries());
              return result;
          } catch (final CloneNotSupportedException e) {
              final IllegalArgumentException iae = new IllegalArgumentException("Cannot clone feed");
              iae.initCause(e);
              throw iae;
          }
      }
docs: <p>
  Combine the entries in two feeds into a single feed.
  </p>
  
  <p>
  The returned feed will have the same data as the newFeed parameter, with the entries from
  originalFeed appended to the end of its entries.
  </p>
  
  @param originalFeed
  @param newFeed
  @return