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1
19
20 package com.sslexplorer.rss;
21
22 import java.io.BufferedReader  ;
23 import java.io.IOException ;
24 import java.io.InputStream ;
25 import java.io.InputStreamReader ;
26 import java.net.MalformedURLException ;
27 import java.net.URL ;
28 import java.net.URLConnection ;
29 import java.text.DateFormat ;
30 import java.util.ArrayList ;
31 import java.util.Collection ;
32 import java.util.Date ;
33 import java.util.HashMap ;
34 import java.util.List ;
35 import java.util.Map ;
36
37 import org.apache.commons.logging.Log;
38 import org.apache.commons.logging.LogFactory;
39
40 import com.sslexplorer.boot.Util;
41 import com.sun.syndication.io.SyndFeedInput;
42
43
48 public final class FeedManager implements Runnable {
49
50
53 public static final int CONNECT_TIMEOUT = 30000;
54
55
58 public static final int READ_TIMEOUT = 30000;
59
60 private static final Log log = LogFactory.getLog(FeedManager.class);
61 private static final int ONE_DAY_MILLIS = 1000 * 60 * 60 * 24;
62 private static final int FOUR_HOURS_MILLIS = 1000 * 60 * 60 * 4;
63 private static final String HOME_URL = "http://download.3sp.com/";
64 private static final String FEED_3SP_URL = HOME_URL + "feeds/";
65
66 private Map <String , Feed> feeds;
67 private List <String > availableFeeds;
68 private boolean running = false;
69 private Thread thread;
70 private int interval = ONE_DAY_MILLIS;
71 private URL baseLocation;
72
73 private static FeedManager instance;
74
75
80 protected FeedManager(URL baseLocation) {
81 this.baseLocation = baseLocation;
82 feeds = new HashMap <String , Feed>();
83 availableFeeds = new ArrayList <String >();
84 }
85
86
91 public static FeedManager getInstance() {
92 if (instance == null) {
93 try {
94 URL baseLocation = new URL (System.getProperty("sslexplorer.rssFeeds.baseLocation", FEED_3SP_URL));
95 instance = new FeedManager(baseLocation);
96 }
97 catch(MalformedURLException murle) {
98 try {
99 URL baseLocation = new URL (FEED_3SP_URL);
100 instance = new FeedManager(baseLocation);
101 }
102 catch(MalformedURLException murle2) {
103 throw new Error ("Invalid default feed location.");
105 }
106 }
107 }
108 return instance;
109 }
110
111
116 public boolean isUpdating() {
117 return running;
118 }
119
120
125 public void startUpdating() {
126 if (running) {
127 throw new IllegalStateException ("Already updating.");
128 }
129 try {
130 loadAvailable();
131 }
132 catch(Exception e) {
133 log.error("Failed to get initial feeds. Next update attempt will occur in 4 hours", e);
134 interval = FOUR_HOURS_MILLIS;
135 }
136
137 thread = new Thread (this, "FeedManager");
138 thread.setPriority(Thread.MIN_PRIORITY);
139 running = true;
140
141 if (!isTestMode()) {
142 thread.start();
143 }
144 }
145
146 private boolean isTestMode() {
147 return Boolean.valueOf(System.getProperty("sslexplorer.testing", "false"));
148 }
149
150 public void run() {
151 try {
152 while (running) {
153
154 if (!running)
155 break;
156
157 if (log.isInfoEnabled())
158 log.info("Checking for feed updates");
159
160 try {
161 retrieveFeeds();
162 interval = ONE_DAY_MILLIS;
163 }
164 catch (Exception e) {
165 log.error("Failed to check for updated feeds. Will check again in 4 hours");
166 interval = FOUR_HOURS_MILLIS;
167 }
168 sleep(interval);
169 }
170 } catch(InterruptedException ie) {
171
172 } finally {
173 running = false;
174 if(log.isInfoEnabled()) {
175 log.info("Stopped checking for RSS updates");
176 }
177 }
178 }
179
180
185 public void stopUpdating() {
186 if (running) {
187 running = false;
188 synchronized (this) {
189 thread.interrupt();
190 }
191 } else {
192 if(!isTestMode()) {
193 throw new IllegalStateException ("Not updating.");
194 }
195 }
196 }
197
198
204 public Feed getFeed(String feedName) {
205
206 synchronized (feeds) {
207 if (!feeds.containsKey(feedName) && !feedName.equals("${rssFeed}") &&
208 availableFeeds.contains(feedName)) {
209 try {
210 Feed feed = new Feed(feedName, new SyndFeedInput(), new URL (baseLocation, feedName + ".xml"));
211 feeds.put(feedName, feed);
212 feed.load();
213 return feed;
214 } catch (Exception ex) {
215 log.error("Failed to load feed.", ex);
216 }
217 }
218 return (Feed) feeds.get(feedName);
219 }
220 }
221
222 protected Collection <String > getAvailableFeedNames() {
223 return availableFeeds;
224 }
225
226 private static void sleep(int checkAgainIn) throws InterruptedException {
227 if (log.isInfoEnabled())
228 log.info("Finished checking for updates / feeds, next check will occur at " + getDateAsString(checkAgainIn));
229 Thread.sleep(checkAgainIn);
230 }
231
232 private static String getDateAsString(int checkAgainIn) {
233 return DateFormat.getDateTimeInstance().format(new Date (System.currentTimeMillis() + checkAgainIn));
234 }
235
236 protected void retrieveFeeds() throws IOException {
237
238 if (log.isInfoEnabled())
239 log.info("Retrieving RSS feeds");
240
241 Map <String , Feed> updatedFeeds = new HashMap <String , Feed>();
242 synchronized (feeds) {
243 for (String feedName : availableFeeds) {
244 try {
245 Feed feed = new Feed(feedName, new SyndFeedInput(), new URL (baseLocation, feedName + ".xml"));
246 updatedFeeds.put(feedName, feed);
247 feed.load();
248 } catch (Exception ex) {
249 log.error("Failed to load feed.", ex);
250 }
251 }
252 feeds = updatedFeeds;
253 }
254 }
255
256 protected void loadAvailable() throws IOException {
257 URL location = new URL (baseLocation, "index.txt");
258
259 availableFeeds.clear();
260 URLConnection conx = location.openConnection();
261 conx.setConnectTimeout(CONNECT_TIMEOUT);
262 conx.setReadTimeout(READ_TIMEOUT);
263
264 if (log.isInfoEnabled()) {
265 log.info("Retrieving RSS feeds index from " + location);
266 }
267 InputStream inputStream = null;
268 try {
269 inputStream = conx.getInputStream();
270 BufferedReader reader = new BufferedReader (new InputStreamReader (inputStream));
271 String line;
272 while ( ( line = reader.readLine() ) != null) {
273 availableFeeds.add(line);
274 }
275 } finally {
276 Util.closeStream(inputStream);
277 }
278 if (log.isInfoEnabled())
279 log.info("There are " + availableFeeds.size() + " available feeds");
280 }
281 } |
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