org.jasig.portlet.calendar.processor.RssContentProcessorImpl.java Source code

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Here is the source code for org.jasig.portlet.calendar.processor.RssContentProcessorImpl.java

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/**
 * Licensed to Apereo under one or more contributor license
 * agreements. See the NOTICE file distributed with this work
 * for additional information regarding copyright ownership.
 * Apereo licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file
 * except in compliance with the License.  You may obtain a
 * copy of the License at the following location:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.jasig.portlet.calendar.processor;

import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import net.fortuna.ical4j.model.DateTime;
import net.fortuna.ical4j.model.PropertyList;
import net.fortuna.ical4j.model.component.VEvent;
import net.fortuna.ical4j.model.property.Description;
import net.fortuna.ical4j.model.property.DtStart;
import net.fortuna.ical4j.model.property.Summary;
import net.fortuna.ical4j.model.property.Uid;
import net.fortuna.ical4j.model.property.Url;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.joda.time.Interval;

import com.sun.syndication.feed.rss.Item;
import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.FeedException;
import com.sun.syndication.io.SyndFeedInput;

/**
 * This {@link IContentProcessor} implementation uses Rome to extract
 * {@link CalendarEventSet}s from RSS formatted streams.
 *
 * @author Nicholas Blair, nblair@doit.wisc.edu
 * @version $Header: RssContentProcessorImpl.java Exp $
 */
public class RssContentProcessorImpl implements IContentProcessor<SyndFeed> {

    protected final Log log = LogFactory.getLog(this.getClass());

    public SyndFeed getIntermediateCalendar(Interval interval, InputStream in) {
        try {

            final SyndFeedInput input = new SyndFeedInput();
            final InputStreamReader reader = new InputStreamReader(in);
            final SyndFeed feed = input.build(reader);
            return feed;

        } catch (IllegalArgumentException e) {
            log.error(e.getMessage(), e);
        } catch (FeedException e) {
            log.error(e.getMessage(), e);
        }
        return null;
    }

    /* (non-Javadoc)
     * @see org.jasig.portlet.calendar.adapter.ContentProcessor#getEvents(java.lang.Long, net.fortuna.ical4j.model.Period, java.io.InputStream)
     */
    public Set<VEvent> getEvents(Interval interval, SyndFeed feed) {
        Set<VEvent> events = new HashSet<VEvent>();

        try {
            @SuppressWarnings("unchecked")
            List<SyndEntry> entries = (List<SyndEntry>) feed.getEntries();
            for (SyndEntry entry : entries) {
                PropertyList props = new PropertyList();

                // Attempt to use the pubDate element as the start date for this
                // event.  RSS feeds don't really give us anything to use
                // for an end date.
                Date start = null;
                if (entry.getPublishedDate() != null) {
                    start = entry.getPublishedDate();
                }

                // we only want to add this feed if it's in the desired time period
                if (start != null && interval.contains(start.getTime())) {

                    props.add(new DtStart(new DateTime(start), true));
                    props.add(new Summary(entry.getTitle()));
                    props.add(new Description(entry.getDescription().getValue()));

                    // use the RSS item Guid as the Uid for this event
                    String guid = null;
                    if (entry instanceof Item && ((Item) entry).getGuid() != null) {
                        guid = ((Item) entry).getGuid().getValue();
                        props.add(new Uid(guid));
                    }

                    // try to find a link for this event
                    if (entry.getLink() != null) {
                        try {
                            props.add(new Url(new URI(entry.getLink())));
                        } catch (URISyntaxException e1) {
                        }
                    }

                    // construct and add the new calendar event
                    VEvent event = new VEvent(props);
                    events.add(event);
                }

            }

        } catch (IllegalArgumentException e) {
            log.error(e.getMessage(), e);
        }

        // return the list of matching calendar events
        return events;
    }

}