/*
* Copyright 2004 Sun Microsystems, Inc.
*
* Licensed 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
*
* 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 com.sun.syndication.samples;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;
import java.util.ArrayList;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.IOException;
import com.sun.syndication.feed.synd.SyndFeedI;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedOutput;
import com.sun.syndication.io.SyndFeedInput;
/**
* It aggregates a list of RSS/Atom feeds (they can be of different types)
* into a single feed of the specified type.
* <p>
* @author Alejandro Abdelnur
*
*/
public class FeedAggregator {
public static void main(String[] args) {
boolean ok = false;
if (args.length>=2) {
try {
String outputType = args[0];
SyndFeedI aggrFeed = new SyndFeed();
aggrFeed.setFeedType(outputType);
aggrFeed.setTitle("Aggregated Feed");
aggrFeed.setDescription("Anonymous Aggregated Feed");
aggrFeed.setAuthor("anonymous");
aggrFeed.setLink("http://www.anonymous.com");
List entries = new ArrayList();
aggrFeed.setEntries(entries);
for (int i=1;i<args.length;i++) {
URL feedUrl = new URL(args[i]);
SyndFeedInput input = new SyndFeedInput();
SyndFeedI feed = input.build(getFeedReader(feedUrl));
entries.addAll(feed.getEntries());
}
SyndFeedOutput output = new SyndFeedOutput();
output.output(aggrFeed,new PrintWriter(System.out));
ok = true;
}
catch (Exception ex) {
System.out.println("ERROR: "+ex.getMessage());
}
}
if (!ok) {
System.out.println();
System.out.println("FeedAggregator aggregates different feeds into a single one.");
System.out.println("The first parameter must be the feed type for the aggregated feed.");
System.out.println(" [valid values are: rss_0.9, rss_0.91, rss_0.92, rss_0.93, ]");
System.out.println(" [ rss_0.94, rss_1.0, rss_2.0 & atom_0.3 ]");
System.out.println("The second to last parameters are the URLs of feeds to aggregate.");
System.out.println();
}
}
// To handle charset encoding of incoming feed properly
private static final Pattern CHARSET_PATTERN = Pattern.compile("charset=([.[^; ]]*)");
private static Reader getFeedReader(URL feedUrl) throws IOException {
Reader reader;
URLConnection conn = feedUrl.openConnection();
if (feedUrl.getProtocol().equals("http") || feedUrl.getProtocol().equals("https")) {
// Finds out server charset encoding based on HTTP spec
String contentTypeHeader = conn.getContentType();
String encoding = "ISO-8859-1";
if (contentTypeHeader!=null) {
Matcher matcher = CHARSET_PATTERN.matcher(contentTypeHeader);
if (matcher.find()) {
encoding = matcher.group(1);
}
}
reader = new InputStreamReader(conn.getInputStream(),encoding);
}
else {
// Goes with plartform's default charset encoding
reader = new InputStreamReader(conn.getInputStream());
}
return reader;
}
}