The HttpURLFeedFetcher class does the actual HTTP request. It relies on the FeedInfoCacheI interface which stores information about each feed required for conditional gets. Currently there is a single implementation of FeedInfoCacheI supplied: HashMapFeedInfoCache.
The basic usage of FeedFetcher is as follows:
FeedFetcherCache feedInfoCache = HashMapFeedInfoCache.getInstance();
FeedFetcher feedFetcher = new HttpURLFeedFetcher(feedInfoCache);
SyndFeed feed = feedFetcher.retrieveFeed(new URL("http://blogs.sun.com/roller/rss/pat"));
System.out.println(feed);Any subsequent fetches of http://blogs.sun.com/roller/rss/pat by any FeedFetcher using feedInfoCache will now only retrieve the feed if it has changed.
FeedFetcher can be used without a cache if required. Simply create it using the zero-parameter constructor:
FeedFetcher feedFetcher = new HttpURLFeedFetcher();
A more complete sample (including the use of listener on Fetcher events) is included in the Rome Fetcher project
Note that there has been considerable discussion on the rome-dev list about the best way to manage the creation of the feed fetcher. Currently the client code needs to be responsible for creating specific implementations of the FeedFetcherI interface.