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1
27
28 package storagebin;
29
30 import java.sql.*;
31 import javax.sql.*;
32 import java.util.*;
33 import javax.ejb.*;
34 import javax.naming.*;
35
36
37 public class StorageBinBean implements EntityBean, StorageBinRemoteBusiness {
38 private static final String  dbName = "jdbc/pointbase";
39 private String storageBinId;
40 private String widgetId;
41 private int quantity;
42 private EntityContext context;
43 private Connection con;
44
45 public String getWidgetId() {
46 return widgetId;
47 }
48
49 public int getQuantity() {
50 return quantity;
51 }
52
53 public String ejbCreate(String storageBinId, String widgetId, int quantity)
54 throws CreateException {
55 try {
56 insertRow(storageBinId, widgetId, quantity);
57 } catch (Exception ex) {
58 throw new EJBException("ejbCreate: " + ex.getMessage());
59 }
60
61 this.storageBinId = storageBinId;
62 this.widgetId = widgetId;
63 this.quantity = quantity;
64
65 return storageBinId;
66 }
67
68 public String ejbFindByPrimaryKey(String primaryKey)
69 throws FinderException {
70 boolean result;
71
72 try {
73 result = selectByPrimaryKey(primaryKey);
74 } catch (Exception ex) {
75 throw new EJBException("ejbFindByPrimaryKey: " + ex.getMessage());
76 }
77
78 if (result) {
79 return primaryKey;
80 } else {
81 throw new ObjectNotFoundException("Row for id " + primaryKey +
82 " not found.");
83 }
84 }
85
86 public String ejbFindByWidgetId(String widgetId) throws FinderException {
87 String storageBinId;
88
89 try {
90 storageBinId = selectByWidgetId(widgetId);
91 } catch (Exception ex) {
92 throw new EJBException("ejbFindByWidgetId: " + ex.getMessage());
93 }
94
95 return storageBinId;
96 }
97
98 public void ejbRemove() {
99 try {
100 deleteRow(storageBinId);
101 } catch (Exception ex) {
102 throw new EJBException("ejbRemove: " + ex.getMessage());
103 }
104 }
105
106 public void setEntityContext(EntityContext context) {
107 this.context = context;
108 }
109
110 public void unsetEntityContext() {
111 }
112
113 public void ejbActivate() {
114 storageBinId = (String ) context.getPrimaryKey();
115 }
116
117 public void ejbPassivate() {
118 storageBinId = null;
119 }
120
121 public void ejbLoad() {
122 try {
123 loadRow();
124 } catch (Exception ex) {
125 throw new EJBException("ejbLoad: " + ex.getMessage());
126 }
127 }
128
129 public void ejbStore() {
130 try {
131 storeRow();
132 } catch (Exception ex) {
133 throw new EJBException("ejbLoad: " + ex.getMessage());
134 }
135 }
136
137 public void ejbPostCreate(String storageBinId, String widgetId, int quantity) {
138 }
139
140
141 private void makeConnection() {
142 try {
143 InitialContext ic = new InitialContext();
144 DataSource ds = (DataSource) ic.lookup(dbName);
145
146 con = ds.getConnection();
147 } catch (Exception ex) {
148 throw new EJBException("Unable to connect to database. " +
149 ex.getMessage());
150 }
151 }
152
153 private void releaseConnection() {
154 try {
155 con.close();
156 } catch (SQLException ex) {
157 throw new EJBException("releaseConnection: " + ex.getMessage());
158 }
159 }
160
161 private void insertRow(String storageBinId, String widgetId, int quantity)
162 throws SQLException {
163 makeConnection();
164
165 String insertStatement = "insert into storagebin values ( ? , ? , ? )";
166 PreparedStatement prepStmt = con.prepareStatement(insertStatement);
167
168 prepStmt.setString(1, storageBinId);
169 prepStmt.setString(2, widgetId);
170 prepStmt.setInt(3, quantity);
171
172 prepStmt.executeUpdate();
173 prepStmt.close();
174 releaseConnection();
175 }
176
177 private void deleteRow(String storageBinId) throws SQLException {
178 makeConnection();
179
180 String deleteStatement =
181 "delete from storagebin where storagebinid = ? ";
182 PreparedStatement prepStmt = con.prepareStatement(deleteStatement);
183
184 prepStmt.setString(1, storageBinId);
185 prepStmt.executeUpdate();
186 prepStmt.close();
187 releaseConnection();
188 }
189
190 private boolean selectByPrimaryKey(String primaryKey)
191 throws SQLException {
192 makeConnection();
193
194 String selectStatement =
195 "select storagebinid " + "from storagebin where storagebinid = ? ";
196 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
197
198 prepStmt.setString(1, primaryKey);
199
200 ResultSet rs = prepStmt.executeQuery();
201 boolean result = rs.next();
202
203 prepStmt.close();
204 releaseConnection();
205
206 return result;
207 }
208
209 private String selectByWidgetId(String widgetId) throws SQLException {
210 makeConnection();
211
212 String storageBinId;
213
214 String selectStatement =
215 "select storagebinid " + "from storagebin where widgetid = ? ";
216 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
217
218 prepStmt.setString(1, widgetId);
219
220 ResultSet rs = prepStmt.executeQuery();
221
222 if (rs.next()) {
223 storageBinId = rs.getString(1);
224 } else {
225 storageBinId = null;
226 }
227
228 prepStmt.close();
229 releaseConnection();
230
231 return storageBinId;
232 }
233
234 private void loadRow() throws SQLException {
235 makeConnection();
236
237 String selectStatement =
238 "select widgetId, quantity " +
239 "from storagebin where storagebinid = ? ";
240 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
241
242 prepStmt.setString(1, this.storageBinId);
243
244 ResultSet rs = prepStmt.executeQuery();
245
246 if (rs.next()) {
247 this.widgetId = rs.getString(1);
248 this.quantity = rs.getInt(2);
249 prepStmt.close();
250 } else {
251 prepStmt.close();
252 throw new NoSuchEntityException("Row for storageBinId " +
253 storageBinId + " not found in database.");
254 }
255
256 releaseConnection();
257 }
258
259 private void storeRow() throws SQLException {
260 makeConnection();
261
262 String updateStatement =
263 "update storagebin set widgetId = ? , " + "quantity = ? " +
264 "where storagebinid = ?";
265 PreparedStatement prepStmt = con.prepareStatement(updateStatement);
266
267 prepStmt.setString(1, widgetId);
268 prepStmt.setInt(2, quantity);
269 prepStmt.setString(3, storageBinId);
270
271 int rowCount = prepStmt.executeUpdate();
272
273 prepStmt.close();
274
275 if (rowCount == 0) {
276 throw new EJBException("Storing row for storageBinId " +
277 storageBinId + " failed.");
278 }
279
280 releaseConnection();
281 }
282 }
283 |
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