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54
106
107 package com.Yasna.forum.database;
108
109 import java.util.*;
110 import java.sql.*;
112 import com.Yasna.forum.*;
113
114
117 public class DbUserMessagesIterator implements Iterator, ListIterator {
118
119
120 private static final String  USER_MESSAGES =
121 "SELECT messageID, yazdMessage.threadID FROM yazdMessage,yazdForum,yazdThread WHERE " +
122 "yazdMessage.userID=? AND yazdForum.forumID=? AND " +
123 "yazdThread.forumID=yazdForum.forumID AND " +
124 "yazdMessage.threadID=yazdThread.threadID order by yazdMessage.creationDate desc";
125
126 private int currentIndex = -1;
127 private int [] messages;
128 private int [] threads;
130 private Forum forum;
131
132 private DbForumFactory factory;
133
134 protected DbUserMessagesIterator(DbForumFactory factory, User user, Forum forum)
135 {
136 this.factory = factory;
137 this.forum = forum;
138 ArrayList tempMessages = new ArrayList();
141 ArrayList tempThreads = new ArrayList();
142 Connection con = null;
143 PreparedStatement pstmt = null;
144 try {
145 con = DbConnectionManager.getConnection();
146 pstmt = con.prepareStatement(USER_MESSAGES);
147 pstmt.setInt(1, user.getID());
148 pstmt.setInt(2, forum.getID());
149 ResultSet rs = pstmt.executeQuery();
150 while (rs.next()) {
151 tempMessages.add(new Integer (rs.getInt(1)));
152 tempThreads.add(new Integer (rs.getInt(2)));
153 }
154 }
155 catch( SQLException sqle ) {
156 System.err.println("Error in DbUserMessagesIterator:constructor()-" + sqle);
157 sqle.printStackTrace();
158 }
159 finally {
160 try { pstmt.close(); }
161 catch (Exception e) { e.printStackTrace(); }
162 try { con.close(); }
163 catch (Exception e) { e.printStackTrace(); }
164 }
165 messages = new int[tempMessages.size()];
167 for (int i=0; i<messages.length; i++) {
168 messages[i] = ((Integer )tempMessages.get(i)).intValue();
169 }
170 threads = new int[tempThreads.size()];
172 for (int i=0; i<threads.length; i++) {
173 threads[i] = ((Integer )tempThreads.get(i)).intValue();
174 }
175 }
176 protected DbUserMessagesIterator(DbForumFactory factory, User user, Forum forum, int startIndex, int numResults)
177 {
178 this.factory = factory;
179 this.forum = forum;
180 int[] tempMessages = new int[numResults];
183 int[] tempThreads = new int[numResults];
184
185 Connection con = null;
186 PreparedStatement pstmt = null;
187 int messageCount = 0;
188
189 try {
190 con = DbConnectionManager.getConnection();
191 pstmt = con.prepareStatement(USER_MESSAGES);
192 pstmt.setInt(1, user.getID());
193 pstmt.setInt(2, forum.getID());
194 ResultSet rs = pstmt.executeQuery();
195 for (int i=0; i<startIndex; i++) {
197 rs.next();
198 }
199 for (int i=0; i<numResults; i++) {
201 if (rs.next()) {
202 tempMessages[messageCount] = rs.getInt(1);
203 tempThreads[messageCount] = rs.getInt(2);
204 messageCount++;
205 }
206 else {
207 break;
208 }
209 }
210 }
211 catch( SQLException sqle ) {
212 System.err.println("Error in DbUserMessagesIterator (2): constructor()-" + sqle);
213 }
214 finally {
215 try { pstmt.close(); }
216 catch (Exception e) { e.printStackTrace(); }
217 try { con.close(); }
218 catch (Exception e) { e.printStackTrace(); }
219 }
220 messages = new int[messageCount];
221 for (int i=0; i<messageCount; i++) {
222 messages[i] = tempMessages[i];
223 }
224 threads = new int[messageCount];
225 for (int i=0; i<messageCount; i++) {
226 threads[i] = tempThreads[i];
227 }
228 }
229
230
233 public boolean hasNext() {
234 return (currentIndex+1 < messages.length);
235 }
236
237
240 public boolean hasPrevious() {
241 return (currentIndex > 0);
242 }
243
244
247 public Object next() throws java.util.NoSuchElementException {
248 ForumMessage message = null;
249 currentIndex++;
250 if (currentIndex >= messages.length) {
251 throw new java.util.NoSuchElementException ();
252 }
253 try {
254 message = forum.getThread(threads[currentIndex]).getMessage(messages[currentIndex]);
255 }
256 catch (ForumThreadNotFoundException ftnfe) {
257 ftnfe.printStackTrace();
258 }
259 catch (ForumMessageNotFoundException fmnfe) {
260 fmnfe.printStackTrace();
261 }
262 return message;
263 }
264
265
271 public void add(Object o) throws UnsupportedOperationException {
272 throw new UnsupportedOperationException ();
273 }
274
275
281 public void remove() {
282 throw new UnsupportedOperationException ();
283 }
284
285
291 public void set(Object o) throws UnsupportedOperationException {
292 throw new UnsupportedOperationException ();
293 }
294
295
298 public int nextIndex() {
299 return currentIndex+1;
300 }
301
302
305 public Object previous() throws java.util.NoSuchElementException {
306 ForumMessage message = null;
307 currentIndex--;
308 if (currentIndex < 0) {
309 currentIndex++;
310 throw new java.util.NoSuchElementException ();
311 }
312 try {
313 message = forum.getThread(threads[currentIndex]).getMessage(messages[currentIndex]);
314 }
315 catch (ForumThreadNotFoundException ftnfe) {
316 ftnfe.printStackTrace();
317 }
318 catch (ForumMessageNotFoundException fmnfe) {
319 fmnfe.printStackTrace();
320 }
321 return message;
322 }
323
324
327 public int previousIndex() {
328 return currentIndex-1;
329 }
330 }
331 |
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