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1
27
28 package bank;
29
30 import java.math.BigDecimal  ;
31 import java.sql.Connection ;
32 import java.sql.PreparedStatement ;
33 import java.sql.ResultSet ;
34 import java.sql.SQLException ;
35 import java.util.ArrayList ;
36 import java.util.Collection ;
37 import java.util.Iterator ;
38 import javax.ejb.*;
39
40
45 public class SavingsAccountBean implements EntityBean, SavingsAccountRemoteBusiness {
46 private EntityContext context;
47 private Connection con;
48 private String id;
49 private String firstName;
50 private String lastName;
51 private BigDecimal balance;
52
53
60 public void setEntityContext(EntityContext aContext) {
61 context = aContext;
62 }
63
64
67 public void ejbActivate() {
68 id = (String )context.getPrimaryKey();
69 }
70
71
74 public void ejbPassivate() {
75 id = null;
76 }
77
78
81 public void ejbRemove() {
82 try{
83 deleteRow(id);
84 }catch(SQLException ex){
85 throw new EJBException("ejbRemove: " + ex.getMessage());
86 }
87 }
88
89
92 public void unsetEntityContext() {
93 context = null;
94 }
95
96
99 public void ejbLoad() {
100 try{
102 loadRow();
103 }catch(SQLException ex){
104 throw new EJBException("ejbLoad() " + ex.getMessage());
105 }
106
107 }
108
109
112 public void ejbStore() {
113 try{
115 storeRow();
116 }catch(SQLException ex){
117 throw new EJBException("ejbStore " + ex.getMessage());
118 }
119 }
120
121
123
126 public java.lang.String ejbFindByPrimaryKey(java.lang.String aKey) throws FinderException {
127 boolean result;
131 try{
132 result = selectByPrimaryKey(aKey);
133 }catch(SQLException ex){
134 throw new EJBException("ejbFindByPrimaryKey: " + ex.getMessage());
135 }
136 if(result){
137 return aKey;
138 }else{
139 throw new ObjectNotFoundException("Account for id " + aKey + " not found.");
140 }
141 }
142
143 public java.lang.String ejbCreate(java.lang.String id, java.lang.String firstName, java.lang.String lastName, java.math.BigDecimal balance) throws CreateException {
144 if(balance.signum() == -1){
146 throw new CreateException("A negative initial balance is not allowed.");
147 }
148 try{
149 insertRow(id, firstName, lastName, balance);
150 }catch(SQLException ex){
151 throw new EJBException("ejbCreate: " + ex.getMessage());
152 }
153 this.id = id;
154 this.firstName = firstName;
155 this.lastName = lastName;
156 this.balance = balance;
157 return id;
158 }
159
160 public void ejbPostCreate(java.lang.String id, java.lang.String firstName, java.lang.String lastName, java.math.BigDecimal balance) throws CreateException {
161 }
163
164 private javax.sql.DataSource getSavingsAccountDB() throws javax.naming.NamingException {
165 javax.naming.Context c = new javax.naming.InitialContext ();
166 return (javax.sql.DataSource ) c.lookup("java:comp/env/jdbc/pointbase");
167 }
168
169 public String getId() {
170 return id;
171 }
172
173 public void setId(String id) {
174 this.id = id;
175 }
176
177 public String getFirstName() {
178 return firstName;
179 }
180
181 public void setFirstName(String firstName) {
182 this.firstName = firstName;
183 }
184
185 public String getLastName() {
186 return lastName;
187 }
188
189 public void setLastName(String lastName) {
190 this.lastName = lastName;
191 }
192
193 public BigDecimal getBalance() {
194 return balance;
195 }
196
197 public void setBalance(BigDecimal balance) {
198 this.balance = balance;
199 }
200
201 public void credit(BigDecimal credit){
202 balance = balance.add(credit);
203 }
204
205 public void debit(BigDecimal amount) throws InsufficientBalanceException {
207 if (balance.compareTo(amount) == -1) {
208 throw new InsufficientBalanceException();
209 }
210
211 balance = balance.subtract(amount);
212 }
213
214 private void makeConnection(){
215 try{
216 con = getSavingsAccountDB().getConnection();
217 }catch(Exception ex){
218 throw new EJBException("Unable to connect to database. " +
219 ex.getMessage());
220 }
221 }
222
223 private void releaseConnection(){
224 try{
225 con.close();
226 }catch(SQLException ex){
227 throw new EJBException("Unable to connect to database. " +
228 ex.getMessage());
229 }
230 }
231
232
234 public java.util.Collection ejbFindInRange(BigDecimal low, BigDecimal high) throws FinderException {
235 Collection result;
237 try{
238 result = selectInRange(low, high);
239 }catch(SQLException ex){
240 throw new EJBException("ejbFindByInRange" + ex.getMessage());
241 }
242 return result;
243 }
244
245 public java.util.Collection ejbFindByLastName(java.lang.String lastName) throws FinderException {
246 Collection result;
248 try{
249 result = selectByLastName(lastName);
250 }catch(SQLException ex){
251 throw new EJBException("ejbFindByLastName" + ex.getMessage());
252 }
253 return result;
254 }
255
256 public void ejbHomeChargeForLowBalance(BigDecimal minimumBalance,
258 BigDecimal charge) throws InsufficientBalanceException {
259 SavingsAccountRemoteHome home = (SavingsAccountRemoteHome)context.getEJBHome();
260 try{
261 Collection c =
262 home.findInRange(new BigDecimal (0.00),
263 minimumBalance.subtract(new BigDecimal (0.01)));
264 Iterator it = c.iterator();
265 while(it.hasNext()){
266 SavingsAccountRemote account = (SavingsAccountRemote)it.next();
267 if(account.getBalance().compareTo(charge) == 1){
268 account.debit(charge);
269 }
270 }
271 }catch(Exception ex){
272 throw new EJBException("ejbHomeChargeForLowBalance" + ex.getMessage());
273 }
274 }
275
276
278 private void insertRow(String id, String firstName,
279 String lastName, BigDecimal balance) throws SQLException {
280 makeConnection();
281 String insertStatement = "insert into savingsaccount values ( ? , ? , ? , ? )";
282 PreparedStatement prepStmt = con.prepareStatement(insertStatement);
283
284 prepStmt.setString(1, id);
285 prepStmt.setString(2, firstName);
286 prepStmt.setString(3, lastName);
287 prepStmt.setBigDecimal(4, balance);
288
289 prepStmt.executeUpdate();
290 prepStmt.close();
291 releaseConnection();
292 }
293
294 private void deleteRow(String id) throws SQLException {
295 makeConnection();
296 String deleteStatement = "delete from savingsaccount where id = ?";
297 PreparedStatement prepStmt = con.prepareStatement(deleteStatement);
298 prepStmt.setString(1, id);
299 prepStmt.executeUpdate();
300 prepStmt.close();
301 releaseConnection();
302 }
303
304 private boolean selectByPrimaryKey(String id) throws SQLException {
305 makeConnection();
306 String selectStatement = "select id from savingsaccount where id = ?";
307 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
308 prepStmt.setString(1, id);
309
310 ResultSet rs = prepStmt.executeQuery();
311 boolean result = rs.next();
312
313 releaseConnection();
314 return result;
315 }
316
317 private void loadRow() throws SQLException {
318 makeConnection();
319 String selectString =
320 "select firstname, lastname, balance from savingsaccount where id = ?";
321 PreparedStatement prepStmt = con.prepareStatement(selectString);
322 prepStmt.setString(1, this.id);
323 ResultSet rs = prepStmt.executeQuery();
324
325 if(rs.next()){
326 this.firstName = rs.getString(1);
327 this.lastName = rs.getString(2);
328 this.balance = rs.getBigDecimal(3);
329 prepStmt.close();
330 }else {
331 prepStmt.close();
332 throw new NoSuchEntityException("Row for id " + id +
333 " not found in database");
334 }
335
336 releaseConnection();
337 }
338
339 private void storeRow() throws SQLException {
340 makeConnection();
341 String updateString =
342 "update savingsaccount set firstname = ? , lastname = ? , " +
343 "balance = ? where id = ?";
344 PreparedStatement prepStmt = con.prepareStatement(updateString);
345 prepStmt.setString(1, firstName);
346 prepStmt.setString(2, lastName);
347 prepStmt.setBigDecimal(3, balance);
348 prepStmt.setString(4, id);
349
350 int rows = prepStmt.executeUpdate();
351 prepStmt.close();
352 releaseConnection();
353 if(rows == 0){
354 throw new EJBException("Storing row id " + id + " failed.");
355 }
356 }
357
358 private Collection selectByLastName(String lastName) throws SQLException {
359 makeConnection();
360 String selectStatement = "select id from savingsaccount where lastname = ?";
361 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
362 prepStmt.setString(1, lastName);
363 ResultSet rs = prepStmt.executeQuery();
364 ArrayList accounts = new ArrayList ();
365
366 while(rs.next()){
367 accounts.add(rs.getString(1));
368 }
369 prepStmt.close();
370 releaseConnection();
371 return accounts;
372 }
373
374 private Collection selectInRange(BigDecimal low, BigDecimal high) throws SQLException {
375 makeConnection();
376 String selectStatement = "select id from savingsaccount where balance between ? and ?";
377 PreparedStatement prepStmt = con.prepareStatement(selectStatement);
378 prepStmt.setBigDecimal(1, low);
379 prepStmt.setBigDecimal(2, high);
380
381 ResultSet rs = prepStmt.executeQuery();
382 ArrayList a = new ArrayList ();
383
384 while(rs.next()){
385 a.add(rs.getString(1));
386 }
387 prepStmt.close();
388 releaseConnection();
389 return a;
390 }
391 }
392 |
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