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1
25 package org.nemesis.forum.impl;
26
27 import java.sql.Connection  ;
28 import java.sql.PreparedStatement ;
29 import java.sql.ResultSet ;
30
31 import org.apache.commons.logging.Log;
32 import org.apache.commons.logging.LogFactory;
33 import org.nemesis.forum.Message;
34 import org.nemesis.forum.TreeWalker;
35 import org.nemesis.forum.util.jdbc.DbConnectionManager;
36
42 public class DbTreeWalker implements TreeWalker {
43 static protected Log log = LogFactory.getLog(DbTreeWalker.class);
44
45 private static final String GET_CHILD =
46 "SELECT yazdMessageTree.childID, yazdMessage.creationDate FROM "
47 + "yazdMessageTree, yazdMessage WHERE "
48 + "yazdMessageTree.childID=yazdMessage.messageID AND "
49 + "yazdMessageTree.parentID=? ORDER BY yazdMessage.creationDate";
50 private static final String CHILD_COUNT = "SELECT count(*) FROM yazdMessageTree WHERE parentID=?";
51 private static final String INDEX_OF_CHILD =
52 "SELECT yazdMessageTree.childID, yazdMessage.creationDate "
53 + "FROM yazdMessageTree, yazdMessage WHERE yazdMessageTree.childID=yazdMessage.messageID "
54 + "AND yazdMessageTree.parentID=? ORDER BY yazdMessage.creationDate";
55
56 private static final String GET_CHILD_APPROVED =
57 "SELECT yazdMessageTree.childID, yazdMessage.creationDate FROM "
58 + "yazdMessageTree, yazdMessage WHERE "
59 + "yazdMessageTree.childID=yazdMessage.messageID AND "
60 + "yazdMessageTree.parentID=? AND yazdMessage.approved=? ORDER BY yazdMessage.creationDate";
61 private static final String CHILD_COUNT_APPROVED = "SELECT count(*) FROM yazdMessageTree, yazdMessage WHERE yazdMessageTree.childID=yazdMessage.messageID AND yazdMessageTree.parentID=? AND yazdMessage.approved=? ";
62 private static final String INDEX_OF_CHILD_APPROVED =
63 "SELECT yazdMessageTree.childID, yazdMessage.creationDate "
64 + "FROM yazdMessageTree, yazdMessage WHERE yazdMessageTree.childID=yazdMessage.messageID "
65 + "AND yazdMessageTree.parentID=? AND yazdMessage.approved=? ORDER BY yazdMessage.creationDate";
66
67
68 private DbForumThread thread;
69 private DbForumFactory factory;
70 private boolean approved;
71 private boolean filter=false;
72
73 public DbTreeWalker(DbForumThread thread, DbForumFactory factory) {
74 this.thread = thread;
75 this.factory = factory;
76 }
77
78 public DbTreeWalker(boolean approved, DbForumThread thread, DbForumFactory factory) {
79 this.thread = thread;
80 this.factory = factory;
81 this.approved=approved;
82 this.filter=true;
83 }
84
85
90 public Message getRoot() {
91 return thread.getRootMessage();
92 }
93
94
103 public Message getChild(Message parent, int index) {
104 Message message = null;
105 Connection con = null;
106 PreparedStatement pstmt = null;
107 try {
108 con = DbConnectionManager.getConnection();
109 if(filter){
110 pstmt = con.prepareStatement(GET_CHILD_APPROVED);
111 pstmt.setInt(1, parent.getID());
112 pstmt.setInt(2, approved ? 1:0);
113 }
114 else{
115 pstmt = con.prepareStatement(GET_CHILD);
116 pstmt.setInt(1, parent.getID());
117 }
118
119
120 ResultSet rs = pstmt.executeQuery();
121 while (rs.next() && index > 0) {
122 index--;
123 }
124 if (index == 0) {
125 int messageID = rs.getInt(1);
126 message = thread.getMessage(messageID);
127 }
128 } catch (Exception e) {
129 log.error("Error in DbMessageTreeWalker:getChild(" + index + ")-" , e);
130
131 } finally {
132 try {
133 pstmt.close();
134 } catch (Exception e) {
135 log.error("" , e);
136 }
137 try {
138 con.close();
139 } catch (Exception e) {
140 log.error("" , e);
141 }
142 }
143 return message;
144 }
145
146
147
148
149
156 public int getChildCount(Message parent) {
157 int childCount = 0;
158 Connection con = null;
159 PreparedStatement pstmt = null;
160 try {
161 con = DbConnectionManager.getConnection();
162
163 if(filter){
164 pstmt = con.prepareStatement(CHILD_COUNT_APPROVED);
165 pstmt.setInt(1, parent.getID());
166 pstmt.setInt(2, approved ? 1:0);
167 }
168 else{
169 pstmt = con.prepareStatement(CHILD_COUNT);
170 pstmt.setInt(1, parent.getID());
171 }
172
173 ResultSet rs = pstmt.executeQuery();
174 rs.next();
175 childCount = rs.getInt(1);
176 } catch (Exception e) {
177 log.error("Error in DbTreeWalker:getChildCount()-" ,e);
178
179 } finally {
180 try {
181 pstmt.close();
182 } catch (Exception e) {
183 log.error("" , e);
184 }
185 try {
186 con.close();
187 } catch (Exception e) {
188 log.error("" , e);
189 }
190 }
191 return childCount;
192 }
193
194
199 public int getRecursiveChildCount(Message parent) {
200 int numChildren = 0;
201 int num = getChildCount(parent);
202 numChildren += num;
203 for (int i = 0; i < num; i++) {
204 Message child = getChild(parent, i);
205 if (child != null) {
206 numChildren += getRecursiveChildCount(child);
207 }
208 }
209 return numChildren;
210 }
211
212
215 public int getIndexOfChild(Message parent, Message child) {
216 int index = 0;
217 Connection con = null;
218 PreparedStatement pstmt = null;
219 ResultSet rs = null;
220 try {
221 con = DbConnectionManager.getConnection();
222
223 if(filter){
224 pstmt = con.prepareStatement(INDEX_OF_CHILD_APPROVED);
225 pstmt.setInt(1, parent.getID());
226 pstmt.setInt(2, approved ? 1:0);
227 }
228 else{
229 pstmt = con.prepareStatement(INDEX_OF_CHILD);
230 pstmt.setInt(1, parent.getID());
231 }
232
233
234 rs = pstmt.executeQuery();
235 while (rs.next()) {
236 if (rs.getInt(1) == child.getID()) {
237 break;
238 }
239 index++;
240 }
241 } catch (Exception e) {
242 log.error("Error in DbTreeWalker:getIndexOfChild()-" , e);
243 } finally {
244 try {
245 pstmt.close();
246 } catch (Exception e) {
247 log.error("" , e);
248 }
249 try {
250 con.close();
251 } catch (Exception e) {
252 log.error("" , e);
253 }
254 }
255 return index;
256 }
257
258
265 public boolean isLeaf(Message node) {
266 return (getChildCount(node) == 0);
267 }
268 }
269 |
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