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1
5 package persistentaccount;
6
7 import java.sql.Connection  ;
8 import java.sql.DriverManager ;
9 import java.sql.PreparedStatement ;
10 import java.sql.ResultSet ;
11 import java.sql.SQLException ;
12 import java.util.Collections ;
13 import java.util.Map ;
14 import java.util.WeakHashMap ;
15
16 import org.apache.commons.logging.Log;
17 import org.apache.commons.logging.LogFactory;
18
19 import ve.luz.ica.jackass.component.ApplicationContext;
20 import ve.luz.ica.jackass.component.StatelessContext;
21 import ve.luz.ica.jackass.component.StatelessHook;
22
23 import account.AccountData;
24 import account.AccountManagerPOA;
25 import account.OperationFailed;
26
27
31 public class AccountManagerImpl extends AccountManagerPOA implements StatelessHook
32 {
33 private static final Log LOG = LogFactory.getLog(AccountManagerImpl.class);
34
35 private static final String BALANCE_FIELD = "balance";
36 private static final String NAME_FIELD = "name";
37 private static final String ID_FIELD = "id";
38
39 private static final String ACCOUNT_NOT_FOUND = "Account not found";
40 private static Map accounts = Collections.synchronizedMap(new WeakHashMap ());
41
42 private StatelessContext compContext = null;
43 private ApplicationContext appContext = null;
44 private Connection connection = null;
45
46 private AccountData getAccount(int id) throws Exception
47 {
48 AccountData account = (AccountData) accounts.get(new Integer (id));
49 if (account == null)
50 {
51 try {
52 account = new AccountData();
53 String s = "select id, name, balance from account where id = ?";
54 PreparedStatement ps = connection.prepareStatement(s);
55 ps.setInt(1, id);
56 ResultSet result = ps.executeQuery();
57
58 if (result.next())
59 {
60 account.id = result.getInt(ID_FIELD);
61 account.name = result.getString(NAME_FIELD);
62 account.balance = result.getDouble(BALANCE_FIELD);
63 accounts.put(new Integer (id), account);
64 }
65 else
66 {
67 LOG.error("Account " + id + " not found");
68 throw new Exception (ACCOUNT_NOT_FOUND);
69 }
70 }
71 catch (Exception e)
72 {
73 LOG.error("Unexpected error " + e.getMessage());
74 if (LOG.isDebugEnabled()) LOG.debug("Stack trace follows ", e);
75 throw new Exception (e);
76 }
77 }
78 return account;
79 }
80
81 private void updateAccount(AccountData account) throws Exception
82 {
83 String s = "update account set id = ?, name = ?, balance = ? where id = ?";
84 PreparedStatement ps = connection.prepareStatement(s);
85 ps.setInt(1, account.id);
86 ps.setString(2, account.name);
87 ps.setDouble(3, account.balance);
88 ps.setInt(4, account.id);
89 if (ps.executeUpdate() != 1)
90 {
91 LOG.error("Unexpected error when updating account " + account.id);
92 throw new Exception ("Error when updating account");
93 }
94 }
95
96
99 public void createAccount(int id, String name, double initialBalance) throws OperationFailed
100 {
101 try
102 {
103 AccountData account = new AccountData(id, name, initialBalance);
104 String s = "insert into account (id, name, balance) values (?, ?, ?)";
105 PreparedStatement ps = connection.prepareStatement(s);
106 ps.setInt(1, account.id);
107 ps.setString(2, account.name);
108 ps.setDouble(3, account.balance);
109 if (ps.executeUpdate() != 1)
110 {
111 LOG.error("Unexpected error when updating account " + id);
112 throw new Exception ("Error when updating account");
113 }
114 accounts.put(new Integer (id), account);
115 }
116 catch (Exception e)
117 {
118 throw new OperationFailed(e.getMessage());
119 }
120 }
121
122
125 public void deleteAccount(int id) throws OperationFailed
126 {
127 try
128 {
129 accounts.remove(new Integer (id));
130 String s = "delete account where id = ?";
131 PreparedStatement ps = connection.prepareStatement(s);
132 ps.setInt(1, id);
133 if (ps.executeUpdate() != 1)
134 {
135 LOG.error("Unexpected error when deleting account " + id);
136 throw new Exception ("Error when deleting account");
137 }
138 }
139 catch (Exception e)
140 {
141 throw new OperationFailed(e.getMessage());
142 }
143 }
144
145
148 public void deposit(int id, double amount) throws OperationFailed
149 {
150 try
151 {
152 AccountData account = this.getAccount(id);
153 account.balance += amount;
154 updateAccount(account);
155 }
156 catch (Exception e)
157 {
158 throw new OperationFailed(e.getMessage());
159 }
160 }
161
162
165 public void withdraw(int id, double amount) throws OperationFailed
166 {
167 try
168 {
169 AccountData account = this.getAccount(id);
170 account.balance -= amount;
171 updateAccount(account);
172 }
173 catch (Exception e)
174 {
175 throw new OperationFailed(e.getMessage());
176 }
177 }
178
179
182 public double getBalance(int id) throws OperationFailed
183 {
184 try
185 {
186 AccountData account = this.getAccount(id);
187 return account.balance;
188 }
189 catch (Exception e)
190 {
191 throw new OperationFailed(e.getMessage());
192 }
193 }
194
195
198 public AccountData getAccountData(int id) throws OperationFailed
199 {
200 try
201 {
202 AccountData account = this.getAccount(id);
203 return account;
204 }
205 catch (Exception e)
206 {
207 throw new OperationFailed(e.getMessage());
208 }
209 }
210
211
214 public void jackassSetContexts(ApplicationContext appCtx, StatelessContext compCtx)
215 {
216 this.appContext = appCtx;
217 this.compContext = compCtx;
218 }
219
220
223 public void jackassCreate()
224 {
225 try
226 {
227 String dbDriverClassName = compContext.getProperty("driver_class");
228 Class.forName(dbDriverClassName, true, this.getClass().getClassLoader());
229
230 String connectionString = compContext.getProperty("connection_string");
231 String username = compContext.getProperty("username");
232 String password = compContext.getProperty("password");
233
234 connection = DriverManager.getConnection (connectionString, username, password);
235 }
236 catch (Exception e)
237 {
238 if (LOG.isInfoEnabled()) LOG.info("Error during create " + e.getMessage());
239 if (LOG.isDebugEnabled()) LOG.debug("Stack trace follows ", e);
240 }
241 }
242
243
246 public void jackassRemove()
247 {
248 try
249 {
250 connection.close();
251 }
252 catch (SQLException e)
253 {
254 if (LOG.isInfoEnabled()) LOG.info("Error during remove " + e.getMessage());
255 if (LOG.isDebugEnabled()) LOG.debug("Stack trace follows ", e);
256 }
257 }
258 }
259
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