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1
43 package org.exolab.jms.persistence;
44
45
46 import java.sql.Connection  ;
47 import java.sql.PreparedStatement ;
48 import java.sql.ResultSet ;
49 import java.util.Vector ;
50
51 import org.exolab.jms.authentication.User;
52
53
54
62 class Users {
63
64
67 private static Users _instance;
68
69
72 private static final Object _block = new Object ();
73
74
77 private Users() {
78 }
79
80
88 public static Users instance() {
89 return _instance;
90 }
91
92
97 public static Users initialise() {
98 if (_instance == null) {
99 synchronized (_block) {
100 if (_instance == null) {
101 _instance = new Users();
102 }
103 }
104 }
105 return _instance;
106 }
107
108
115 public synchronized void add(Connection connection,
116 User user)
117 throws PersistenceException {
118
119 PreparedStatement insert = null;
120 try {
121 insert = connection.prepareStatement(
122 "insert into users values (?, ?)");
123 insert.setString(1, user.getUsername());
124 insert.setString(2, user.getPassword());
125 insert.executeUpdate();
126 } catch (Exception error) {
127 throw new PersistenceException("Users.add failed with "
128 + error.toString());
129 } finally {
130 SQLHelper.close(insert);
131 }
132 }
133
134
141 public synchronized void update(Connection connection,
142 User user)
143 throws PersistenceException {
144
145 PreparedStatement update = null;
146 try {
147 update = connection.prepareStatement(
148 "update users set password=? where username=?");
149 update.setString(1, user.getPassword());
150 update.setString(2, user.getUsername());
151 update.executeUpdate();
152 } catch (Exception error) {
153 throw new PersistenceException("Users.add failed with "
154 + error.toString());
155 } finally {
156 SQLHelper.close(update);
157 }
158 }
159
160
168 public synchronized boolean remove(Connection connection,
169 User user)
170 throws PersistenceException {
171
172 boolean success = false;
173 PreparedStatement deleteUsers = null;
174
175 if (user != null) {
176 try {
177 deleteUsers = connection.prepareStatement(
178 "delete from users where username=?");
179 deleteUsers.setString(1, user.getUsername());
180 deleteUsers.executeUpdate();
181 } catch (Exception error) {
182 throw new PersistenceException("Users.remove failed "
183 + error.toString());
184 } finally {
185 SQLHelper.close(deleteUsers);
186 }
187 }
188
189 return success;
190 }
191
192
200 public synchronized User get(Connection connection,
201 User user)
202 throws PersistenceException {
203
204 PreparedStatement getUser = null;
205 ResultSet set = null;
206 User result = null;
207
208 if (user != null) {
209 try {
210 getUser = connection.prepareStatement(
211 "select * from users where username=?");
212 getUser.setString(1, user.getUsername());
213 set = getUser.executeQuery();
214 if (set.next()) {
215 result = new User(set.getString(1), set.getString(2));
216 }
217 } catch (Exception error) {
218 throw new PersistenceException("Users.get failed "
219 + error.toString());
220 } finally {
221 SQLHelper.close(set);
222 SQLHelper.close(getUser);
223 }
224 }
225
226 return result;
227 }
228
229
236 public synchronized Vector getAllUsers(Connection connection)
237 throws PersistenceException {
238
239 PreparedStatement getUsers = null;
240 ResultSet set = null;
241 User user = null;
242 Vector result = new Vector ();
243
244 try {
245 getUsers = connection.prepareStatement(
246 "select * from users");
247 set = getUsers.executeQuery();
248 while (set.next()) {
249 user = new User(set.getString(1), set.getString(2));
250 result.add(user);
251 }
252 } catch (Exception error) {
253 throw new PersistenceException("Users.remove failed "
254 + error.toString());
255 } finally {
256 SQLHelper.close(set);
257 SQLHelper.close(getUsers);
258 }
259
260 return result;
261 }
262
263
266 public synchronized void close() {
267 _instance = null;
268 }
269
270 }
271 |
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