new TimelineController(twitterService, wavelet.getRootBlip(),
twitterWave, robotMessageBundle.getEvents());
try {
// Fetch new tweets from Twitter.
List<Tweet> newTweets = controller.fetch();
appendTweets(wavelet, newTweets);
// Update the latest tweet id, and purge the cache.
WaveSubmittedTweetsCache cache = new WaveSubmittedTweetsCache();
if (!newTweets.isEmpty()) {