FeedDownloader.java

/*
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package org.glassfish.jersey.examples.feedcombiner.manager;

import java.net.URL;
import java.util.Collections;
import java.util.List;
import java.util.function.Function;

import org.slf4j.LoggerFactory;

import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedInput;
import com.sun.syndication.io.XmlReader;

/**
 * This class is used to download entries of the defined URL (URL of the
 * feed).
 * <p>
 * The implemented {@link Function#apply(Object)} is annotated with
 * {@link SuppressWarnings} due to an absence of generic types in
 * {@link SyndFeed}
 * </p>
 *
 * @author Petr Bouda (petr.bouda at oracle.com)
 */
public class FeedDownloader implements Function<URL, List<SyndEntry>> {

    private static org.slf4j.Logger LOG = LoggerFactory.getLogger(FeedDownloader.class.getName());

    @Override
    @SuppressWarnings("unchecked")
    public List<SyndEntry> apply(URL url) {

        try (XmlReader xmlReader = new XmlReader(url)) {
            SyndFeedInput input = new SyndFeedInput();
            SyndFeed feed = input.build(xmlReader);
            return feed.getEntries();
        } catch (Exception e) {
            LOG.warn("An error during downloading and parsing a given feed: " + url, e);
        }
        return Collections.emptyList();
    }
}