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Java > Open Source Codes > org > apache > james > nntpserver > repository > NNTPGroupImpl


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2  * Copyright (c) 2000-2004 The Apache Software Foundation. *
3  * All rights reserved. *
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5  * Licensed under the Apache License, Version 2.0 (the "License"); you *
6  * may not use this file except in compliance with the License. You *
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9  * http://www.apache.org/licenses/LICENSE-2.0 *
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11  * Unless required by applicable law or agreed to in writing, software *
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14  * implied. See the License for the specific language governing *
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17
18 package org.apache.james.nntpserver.repository;
19
20 import org.apache.avalon.excalibur.io.AndFileFilter;
21 import org.apache.avalon.excalibur.io.ExtensionFileFilter;
22 import org.apache.avalon.excalibur.io.InvertedFileFilter;
23 import org.apache.avalon.excalibur.io.IOUtil;
24 import org.apache.avalon.framework.logger.AbstractLogEnabled;
25 import org.apache.james.nntpserver.DateSinceFileFilter;
26
27 import java.io.File JavaDoc;
28 import java.io.FileOutputStream JavaDoc;
29 import java.io.InputStream JavaDoc;
30 import java.io.IOException JavaDoc;
31 import java.util.ArrayList JavaDoc;
32 import java.util.Date JavaDoc;
33 import java.util.Iterator JavaDoc;
34 import java.util.List JavaDoc;
35
36 /**
37  * Group is represented by a directory.
38  * Articles are stored in files with the name of file == article number
39  *
40  */
41 class NNTPGroupImpl extends AbstractLogEnabled implements NNTPGroup {
42
43     /**
44      * The directory to which this group maps.
45      */
46     private final File JavaDoc root;
47
48     /**
49      * The last article number in the group
50      */
51     private int lastArticle;
52
53     /**
54      * The last article number in the group
55      */
56     private int firstArticle;
57
58     /**
59      * The number of articles in the group.
60      */
61     private int numOfArticles;
62
63     /**
64      * Whether the first, last, and total number of articles in the
65      * group have been read from disk.
66      * An instance may collect range info once. This involves disk I/O
67      */
68     private boolean articleRangeInfoCollected = false;
69
70     /**
71      * The sole constructor for this particular NNTPGroupImpl.
72      *
73      * @param root the directory containing the articles
74      */
75     NNTPGroupImpl(File JavaDoc root) {
76         this.root = root;
77     }
78
79     /**
80      * @see org.apache.james.nntpserver.NNTPGroup#getName()
81      */
82     public String JavaDoc getName() {
83         return root.getName();
84     }
85
86     /**
87      * @see org.apache.james.nntpserver.NNTPGroup#getDescription()
88      */
89     public String JavaDoc getDescription() {
90         return getName();
91     }
92
93     /**
94      * @see org.apache.james.nntpserver.NNTPGroup#isPostAllowed()
95      */
96     public boolean isPostAllowed() {
97         return true;
98     }
99
100     /**
101      * Generates the first, last, and number of articles from the
102      * information in the group directory.
103      */
104     private void collectArticleRangeInfo() {
105         if ( articleRangeInfoCollected ) {
106             return;
107         }
108         String JavaDoc[] list = root.list();
109         int first = -1;
110         int last = -1;
111         for ( int i = 0 ; i < list.length ; i++ ) {
112             int num = Integer.parseInt(list[i]);
113             if ( first == -1 || num < first ) {
114                 first = num;
115             }
116             if ( num > last ) {
117                 last = num;
118             }
119         }
120         numOfArticles = list.length;
121         firstArticle = Math.max(first,0);
122         lastArticle = Math.max(last,0);
123         articleRangeInfoCollected = true;
124     }
125
126     /**
127      * @see org.apache.james.nntpserver.NNTPGroup#getNumberOfArticles()
128      */
129     public int getNumberOfArticles() {
130         collectArticleRangeInfo();
131         return numOfArticles;
132     }
133
134     /**
135      * @see org.apache.james.nntpserver.NNTPGroup#getFirstArticleNumber()
136      */
137     public int getFirstArticleNumber() {
138         collectArticleRangeInfo();
139         return firstArticle;
140     }
141
142     /**
143      * @see org.apache.james.nntpserver.NNTPGroup#getLastArticleNumber()
144      */
145     public int getLastArticleNumber() {
146         collectArticleRangeInfo();
147         return lastArticle;
148     }
149
150     /**
151      * @see org.apache.james.nntpserver.NNTPGroup#getArticle(int)
152      */
153     public NNTPArticle getArticle(int number) {
154         File JavaDoc f = new File JavaDoc(root,number + "");
155         return f.exists() ? new NNTPArticleImpl(this, f) : null;
156     }
157
158     /**
159      * @see org.apache.james.nntpserver.NNTPGroup#getArticlesSince(Date)
160      */
161     public Iterator JavaDoc getArticlesSince(Date JavaDoc dt) {
162         File JavaDoc[] f = root.listFiles(new AndFileFilter
163             (new DateSinceFileFilter(dt.getTime()),
164              new InvertedFileFilter(new ExtensionFileFilter(".id"))));
165         List JavaDoc list = new ArrayList JavaDoc();
166         for ( int i = 0 ; i < f.length ; i++ ) {
167             list.add(new NNTPArticleImpl(this, f[i]));
168         }
169         return list.iterator();
170     }
171
172     /**
173      * @see org.apache.james.nntpserver.NNTPGroup#getArticles()
174      */
175     public Iterator JavaDoc getArticles() {
176         File JavaDoc[] f = root.listFiles();
177         List JavaDoc list = new ArrayList JavaDoc();
178         for ( int i = 0 ; i < f.length ; i++ )
179             list.add(new NNTPArticleImpl(this, f[i]));
180         return list.iterator();
181     }
182
183     /**
184      * @see org.apache.james.nntpserver.repository.NNTPGroup#getListFormat()
185      */
186     public String JavaDoc getListFormat() {
187         StringBuffer JavaDoc showBuffer =
188             new StringBuffer JavaDoc(128)
189                 .append(getName())
190                 .append(" ")
191                 .append(getLastArticleNumber())
192                 .append(" ")
193                 .append(getFirstArticleNumber())
194                 .append(" ")
195                 .append((isPostAllowed() ? "y":"n"));
196         return showBuffer.toString();
197     }
198
199     /**
200      * @see org.apache.james.nntpserver.repository.NNTPGroup#getListNewsgroupsFormat()
201      */
202     public String JavaDoc getListNewsgroupsFormat() {
203         StringBuffer JavaDoc showBuffer =
204             new StringBuffer JavaDoc(128)
205                 .append(getName())
206                 .append(" ")
207                 .append(getDescription());
208          return showBuffer.toString();
209     }
210
211     /**
212      * @see org.apache.james.nntpserver.repository.NNTPGroup#addArticle(InputStream)
213      */
214     public NNTPArticle addArticle(InputStream JavaDoc newsStream)
215             throws IOException JavaDoc {
216         File JavaDoc articleFile = null;
217         synchronized (this) {
218             int artNum;
219             if (numOfArticles < 0)
220                 throw new IllegalStateException JavaDoc("NNTP Group is corrupt (articles < 0).");
221             else if (numOfArticles == 0) {
222                 firstArticle = 1;
223                 artNum = 1;
224             } else {
225                 artNum = getLastArticleNumber() + 1;
226             }
227             
228             articleFile = new File JavaDoc(root, artNum + "");
229             articleFile.createNewFile();
230             lastArticle = artNum;
231             numOfArticles++;
232         }
233         if (getLogger().isDebugEnabled()) {
234             getLogger().debug("Copying message to: "+articleFile.getAbsolutePath());
235         }
236         FileOutputStream JavaDoc fout = null;
237         try {
238             fout = new FileOutputStream JavaDoc(articleFile);
239             IOUtil.copy(newsStream,fout);
240             fout.flush();
241         } finally {
242             try {
243                 if (fout != null) {
244                     fout.close();
245                 }
246             } catch (IOException JavaDoc ioe) {
247                 // Ignore this exception so we don't
248 // trash any "real" exceptions
249 }
250         }
251         return new NNTPArticleImpl(this, articleFile);
252     }
253
254 // public NNTPArticle getArticleFromID(String id) {
255 // if ( id == null )
256 // return null;
257 // int idx = id.indexOf('@');
258 // if ( idx != -1 )
259 // id = id.substring(0,idx);
260 // File f = new File(root,id + ".id");
261 // if ( f.exists() == false )
262 // return null;
263 // try {
264 // FileInputStream fin = new FileInputStream(f);
265 // int count = fin.available();
266 // byte[] ba = new byte[count];
267 // fin.read(ba);
268 // fin.close();
269 // String str = new String(ba);
270 // int num = Integer.parseInt(str);
271 // return getArticle(num);
272 // } catch(IOException ioe) {
273 // throw new NNTPException("could not fectch article: "+id,ioe);
274 // }
275 // }
276
277 }
278
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