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1 package org.crazybob.rss;
2
3 import java.util.*;
4 import java.io.*;
5
6 import org.jdom.input.*;
7
8 import org.crazybob.util.NestedException;
9 import org.crazybob.util.EmailUtils;
10
11
15 public class FetchRss {
16
17 FetchRss(String  [] args) throws Exception {
18 File lock = new File("fetchrss.lock");
19 if (!lock.createNewFile()) {
20 System.err.println("Another instance is already running.");
21 System.exit(1);
22 }
23 lock.deleteOnExit();
24 Map oldChannels = readOldChannels();
25 pollFeeds(args, oldChannels);
26 writeOldChannels(oldChannels);
27 }
28
29 private void emailDifferences(Channel old, Channel current)
30 throws IOException {
31 Set oldSet = (old == null) ? Collections.EMPTY_SET :
32 new HashSet(old.getItems());
33 for (Iterator iterator = current.getItems().iterator();
34 iterator.hasNext();) {
35 Item item = (Item) iterator.next();
36 if (!oldSet.contains(item))
37 emailItem(item, EmailUtils.formatFriendlyFrom(current.getTitle()));
38 }
39 }
40
41 private void emailItem(Item item, String channelTitle) throws IOException {
42 Mailer mailer = new Mailer(getProperty("smtp.server"));
43 mailer.send(
44 getProperty("to.address"),
45 getProperty("from.address"),
46 channelTitle + " <" + getProperty("from.address") + ">",
47 item.getTitle(),
48 "<p><a HREF=\"" + item.getLink() + "\">" +
49 item.getLink() + "</a></p><p>" +
50 item.getDescription() + "</p>"
51 );
52 }
53
54 public void pollFeeds(String [] feeds, Map oldChannels) throws IOException,
55 ClassNotFoundException {
56 boolean blogRollerFlag = false;
57
58 for (int i = 0; i < feeds.length; i++) {
59 blogRollerFlag = (feeds[i].substring(0, 3).equalsIgnoreCase("BR:")) ? true : false;
61 try {
62 String link = feeds[i];
63 Channel old = (Channel) oldChannels.get(link);
64 UrlLoader.Response response =
65 new UrlLoader().load((blogRollerFlag == false) ? link : link.substring(3),
66 (old == null) ? null : old.getLastModified());
67 if (response == null)
68 continue;
69 Channel current = new Parser().parse(
70 new SAXBuilder().build(new
71 StringReader(response.getBody())));
72
73 current.setLastModified(response.getLastModified());
74 emailDifferences(old, current);
75 oldChannels.put(link, current);
76
77 if (blogRollerFlag) {
78 String [] blogLinks = new String [current.getItems().size()];
79 int counter = 0;
80 for (Iterator it = current.getItems().iterator(); it.hasNext(); counter++) {
81 Item item = (Item) it.next();
82 blogLinks[counter] = item.getDescription();
83 }
84 pollFeeds(blogLinks, oldChannels);
86 }
87
88 } catch (Exception
89 e) {
90 System.err.println("ERROR. URL: " + feeds[i]);
91 e.printStackTrace();
92 }
93 }
94 }
95
96 private Map readOldChannels() throws IOException, ClassNotFoundException {
97 File channelsFile = getHistoryFile();
98
99 Map oldChannels = null;
100 if (channelsFile.exists()) {
101 ObjectInputStream oIn = new ObjectInputStream(
102 new FileInputStream(channelsFile)
103 );
104 oldChannels = (Map) oIn.readObject();
105 oIn.close();
106 }
107 if (oldChannels == null)
108 oldChannels = new HashMap();
109 return oldChannels;
110 }
111
112 private void writeOldChannels(Map oldChannels) throws IOException {
113 File channelsFile = getHistoryFile();
114
115 ObjectOutputStream oOut = new ObjectOutputStream(
116 new FileOutputStream(channelsFile)
117 );
118 oOut.writeObject(oldChannels);
119 oOut.flush();
120 oOut.close();
121 }
122
123 private File getHistoryFile() {
124 return new File(getProperty("history.file"));
125 }
126
127 private static final Properties properties = new Properties();
128
129 static {
130 try {
131 properties.load(new FileInputStream("./fetchrss.properties"));
132 } catch (Exception e) {
133 throw NestedException.wrap(e);
134 }
135 }
136
137 static String getProperty(String key) {
138 return properties.getProperty(key);
139 }
140
141 public static void main(String [] args) throws Exception {
142 FetchRss fetchRss = new FetchRss(args);
143 }
144 }
145 |
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