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1
51
52 package org.objectweb.jass.examples.travelagency.ejbs;
53
54 import org.objectweb.jass.examples.travelagency.exceptions.DBException;
55 import org
56 .objectweb
57 .jass
58 .examples
59 .travelagency
60 .exceptions
61 .NotEnoughRoomsException;
62 import org
63 .objectweb
64 .jass
65 .examples
66 .travelagency
67 .ejbs
68 .compensations
69 .ReserveRoomsCompensation;
70
71 import javax.ejb.EJBException  ;
72 import javax.ejb.SessionBean ;
73 import javax.ejb.SessionContext ;
74 import javax.naming.Context ;
75 import javax.naming.InitialContext ;
76 import javax.naming.NamingException ;
77 import javax.sql.DataSource ;
78 import javax.activity.opennested.UserOpenNested;
79 import java.sql.Connection ;
80 import java.sql.Statement ;
81 import java.sql.ResultSet ;
82 import java.sql.SQLException ;
83
84
92 public class HotelBean implements SessionBean {
93
94 private UserOpenNested uon = null;
95 private DataSource ds = null;
96
97 public void ejbCreate() throws javax.ejb.CreateException {
98 uon = getUserOpenNested();
99 ds = getDataSource();
100 System.out.println("Hotel stateless EJB created!!!");
101 }
102
103 public void ejbActivate() throws EJBException {
104 }
105
106 public void ejbPassivate() throws EJBException {
107 }
108
109 public void ejbRemove() throws EJBException {
110 uon = null;
111 ds = null;
112 System.out.println("Hotel stateless EJB removed!!!");
113 }
114
115 public void setSessionContext(SessionContext sessionContext)
116 throws EJBException {
117 }
118
119
123 public int getFreeRooms() throws DBException {
124 Connection c = null;
125 Statement stmt = null;
126 ResultSet rs = null;
127 int rooms = -1;
128
129 try {
130 c = ds.getConnection();
131 stmt = c.createStatement();
132 rs = stmt.executeQuery("SELECT rooms FROM departments");
133 if (rs.next()) {
134 rooms = rs.getInt(1);
135 }
136 rs.close();
137 stmt.close();
138 c.close();
139 } catch (SQLException e) {
140 throw new DBException();
141 }
142 return rooms;
143 }
144
145
152 public int reserveRooms(int nRooms)
153 throws NotEnoughRoomsException, DBException {
154 Connection c = null;
155 Statement stmt = null;
156 ResultSet rs = null;
157 int result = -1;
158
159 try {
160 uon.activityBegin(0);
161 c = ds.getConnection();
162 stmt = c.createStatement();
163 rs = stmt.executeQuery("SELECT rooms FROM departments");
164 rs.next();
165 int freeRooms = rs.getInt(1);
166 if ((freeRooms - nRooms) < 0) {
167 rs.close();
168 stmt.close();
169 c.close();
170 uon.activityRollback();
171 throw new NotEnoughRoomsException();
172 } else {
173 stmt.executeUpdate(
174 "UPDATE departments SET rooms = " + (freeRooms - nRooms));
175 ReserveRoomsCompensation compensation =
176 new ReserveRoomsCompensation(this, nRooms);
177 uon.activityCommit(compensation);
178 }
179 rs.close();
180 stmt.close();
181 c.close();
182 result = nRooms;
183 } catch (SQLException e) {
184 try {
185 uon.activityRollback();
186 } catch (Exception e1) {
187 e1.printStackTrace();
188 }
189 throw new DBException();
190 } catch (NotEnoughRoomsException e) {
191 throw e;
192 } catch (Exception e) {
193 e.printStackTrace();
194 }
195 return result;
196 }
197
198
203 public int unreserveRooms(int nRooms) throws DBException {
204 Connection c = null;
205 Statement stmt = null;
206 ResultSet rs = null;
207 int result = -1;
208
209 try {
210 uon.activityBegin(0);
211 c = ds.getConnection();
212 stmt = c.createStatement();
213 rs = stmt.executeQuery("SELECT rooms FROM departments");
214 rs.next();
215 int freeRooms = rs.getInt(1);
216 stmt.executeUpdate(
217 "UPDATE departments SET rooms = " + (freeRooms + nRooms));
218 uon.activityCommit(null);
219 rs.close();
220 stmt.close();
221 c.close();
222 result = nRooms;
223 } catch (SQLException e) {
224 try {
225 uon.activityRollback();
226 } catch (Exception e1) {
227 e1.printStackTrace();
228 }
229 throw new DBException();
230 } catch (Exception e) {
231 e.printStackTrace();
232 }
233 return result;
234 }
235
236
239 private UserOpenNested getUserOpenNested() {
240 UserOpenNested uon = null;
241 Context ctx = null;
242
243 try {
244 ctx = new InitialContext ();
245 uon = (UserOpenNested) ctx.lookup("UserOpenNested");
246 } catch (Exception e) {
247 e.printStackTrace();
248 }
249 return uon;
250 }
251
252
255 private DataSource getDataSource() {
256 Context ctx = null;
257 DataSource ds = null;
258 try {
259 ctx = new InitialContext ();
260 ds = (DataSource ) ctx.lookup("java:/AdaptHotelDS");
261 } catch (NamingException e) {
262 e.printStackTrace();
263 }
264 return ds;
265 }
266 }
267 |
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