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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.net.nntp;
19  
20  import java.util.ArrayList;
21  
22  /**
23   * This is a class that contains the basic state needed for message retrieval and threading.
24   * With thanks to Jamie  Zawinski <jwz@jwz.org>
25   * @author rwinston <rwinston@apache.org>
26   */
27  public class Article implements Threadable {
28      private long articleNumber;
29      private String subject;
30      private String date;
31      private String articleId;
32      private String simplifiedSubject;
33      private String from;
34      private ArrayList<String> references;
35      private boolean isReply = false;
36  
37      public Article kid, next;
38  
39      public Article() {
40          articleNumber = -1; // isDummy
41      }
42  
43      /**
44       * Adds a message-id to the list of messages that this message references (i.e. replies to)
45       * @param msgId
46       */
47      public void addReference(String msgId) {
48          if (msgId == null || msgId.length() == 0) {
49              return;
50          }
51          if (references == null) {
52              references = new ArrayList<String>();
53          }
54          isReply = true;
55          for(String s : msgId.split(" ")) {
56              references.add(s);
57          }
58      }
59  
60      /**
61       * Returns the MessageId references as an array of Strings
62       * @return an array of message-ids
63       */
64      public String[] getReferences() {
65          if (references == null) {
66              return new String[0];
67          }
68          return references.toArray(new String[references.size()]);
69      }
70  
71      /**
72       * Attempts to parse the subject line for some typical reply signatures, and strip them out
73       *
74       */
75      private void simplifySubject() {
76              int start = 0;
77              String subject = getSubject();
78              int len = subject.length();
79  
80              boolean done = false;
81  
82              while (!done) {
83                  done = true;
84  
85                  // skip whitespace
86                  // "Re: " breaks this
87                  while (start < len && subject.charAt(start) == ' ') {
88                      start++;
89                  }
90  
91                  if (start < (len - 2)
92                      && (subject.charAt(start) == 'r' || subject.charAt(start) == 'R')
93                      && (subject.charAt(start + 1) == 'e' || subject.charAt(start + 1) == 'E')) {
94  
95                      if (subject.charAt(start + 2) == ':') {
96                          start += 3; // Skip "Re:"
97                          done = false;
98                      } else if (
99                          start < (len - 2)
100                         &&
101                         (subject.charAt(start + 2) == '[' || subject.charAt(start + 2) == '(')) {
102 
103                         int i = start + 3;
104 
105                         while (i < len && subject.charAt(i) >= '0' && subject.charAt(i) <= '9') {
106                             i++;
107                         }
108 
109                         if (i < (len - 1)
110                             && (subject.charAt(i) == ']' || subject.charAt(i) == ')')
111                             && subject.charAt(i + 1) == ':')
112                         {
113                             start = i + 2;
114                             done = false;
115                         }
116                     }
117                 }
118 
119                 if ("(no subject)".equals(simplifiedSubject)) {
120                     simplifiedSubject = "";
121                 }
122 
123                 int end = len;
124 
125                 while (end > start && subject.charAt(end - 1) < ' ') {
126                     end--;
127                 }
128 
129                 if (start == 0 && end == len) {
130                     simplifiedSubject = subject;
131                 } else {
132                     simplifiedSubject = subject.substring(start, end);
133                 }
134             }
135         }
136 
137     /**
138      * Recursive method that traverses a pre-threaded graph (or tree)
139      * of connected Article objects and prints them out.
140      * @param article the root of the article 'tree'
141      * @param depth the current tree depth
142      */
143     public static void printThread(Article article, int depth) {
144             for (int i = 0; i < depth; ++i) {
145                 System.out.print("==>");
146             }
147             System.out.println(article.getSubject() + "\t" + article.getFrom()+"\t"+article.getArticleId());
148             if (article.kid != null) {
149                 printThread(article.kid, depth + 1);
150             }
151             if (article.next != null) {
152                 printThread(article.next, depth);
153             }
154     }
155 
156     public String getArticleId() {
157         return articleId;
158     }
159 
160     public long getArticleNumberLong() {
161         return articleNumber;
162     }
163 
164     public String getDate() {
165         return date;
166     }
167 
168     public String getFrom() {
169         return from;
170     }
171 
172     public String getSubject() {
173         return subject;
174     }
175 
176     public void setArticleId(String string) {
177         articleId = string;
178     }
179 
180     public void setArticleNumber(long l) {
181         articleNumber = l;
182     }
183 
184     public void setDate(String string) {
185         date = string;
186     }
187 
188     public void setFrom(String string) {
189         from = string;
190     }
191 
192     public void setSubject(String string) {
193         subject = string;
194     }
195 
196 
197 //    @Override
198     public boolean isDummy() {
199         return (articleNumber == -1);
200     }
201 
202 //    @Override
203     public String messageThreadId() {
204         return articleId;
205     }
206 
207 //    @Override
208     public String[] messageThreadReferences() {
209         return getReferences();
210     }
211 
212 //    @Override
213     public String simplifiedSubject() {
214         if(simplifiedSubject == null) {
215             simplifySubject();
216         }
217         return simplifiedSubject;
218     }
219 
220 
221 //    @Override
222     public boolean subjectIsReply() {
223         return isReply;
224     }
225 
226 
227 //    @Override
228     public void setChild(Threadable child) {
229         this.kid = (Article) child;
230         flushSubjectCache();
231     }
232 
233     private void flushSubjectCache() {
234         simplifiedSubject = null;
235     }
236 
237 
238 //    @Override
239     public void setNext(Threadable next) {
240         this.next = (Article)next;
241         flushSubjectCache();
242     }
243 
244 
245 //    @Override
246     public Threadable makeDummy() {
247         return new Article();
248     }
249 
250     @Override
251     public String toString(){ // Useful for Eclipse debugging
252         return articleNumber + " " +articleId + " " + subject;
253     }
254 
255     // DEPRECATED METHODS - for API compatibility only - DO NOT USE
256 
257     @Deprecated
258     public int getArticleNumber() {
259         return (int) articleNumber;
260     }
261 
262     @Deprecated
263     public void setArticleNumber(int a) {
264         articleNumber = a;
265     }
266     @Deprecated
267 
268     public void addHeaderField(String name, String val) {
269     }
270 
271 }