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1
34
35
36 package com.micronova.jsp.tag;
37
38 import java.util.*;
39 import java.util.regex.*;
40 import java.sql.*;
41 import javax.sql.*;
42 import javax.naming.*;
43 import javax.servlet.jsp.*;
44 import javax.servlet.jsp.jstl.core.Config;
45 import org.apache.taglibs.standard.tag.common.sql.TransactionTagSupport;
46 import com.micronova.util.*;
47
48
49
50 public class TransactionTag extends YuzuTag
51 {
52 protected Object  _dataSource;
53 protected int _isolation;
54 protected int _isolationBefore;
55
56 protected Connection _connection;
57 protected boolean _doesOwnConnection;
58
59
60
61 public static Connection openConnection(Object spec) throws Exception
62 {
63 Connection connection = null;
64
65 if (spec instanceof DataSource)
66 {
67 connection = ((DataSource)spec).getConnection();
68 }
69 else
70 {
71 String specString = (String )spec;
72
73 if (specString.startsWith("jdbc:"))
74 {
75 List parts = StringUtil.split(specString, ',');
76
77 int partsLength = parts.size();
78
79 String jdbcURL = parts.get(0).toString();
80 String driverClassName = parts.get(1).toString();
81
82 String user = null;
83 String password = null;
84
85 if (partsLength >= 3)
86 {
87 user = parts.get(2).toString();
88 }
89
90 if (partsLength >= 4)
91 {
92 password = parts.get(3).toString();
93 }
94
95 Class.forName(driverClassName, true, Thread.currentThread().getContextClassLoader()).newInstance();
96
97 if ((user == null) && (password == null))
98 {
99 connection = DriverManager.getConnection(jdbcURL);
100 }
101 else
102 {
103 connection = DriverManager.getConnection(jdbcURL, user, password);
104 }
105 }
106 else
107 {
108 Context context = new InitialContext();
109 Context environment = (Context)context.lookup("java:comp/env");
110
111 DataSource dataSource = (DataSource)environment.lookup(specString);
112
113 connection = dataSource.getConnection();
114 }
115 }
116
117 return connection;
118 }
119
120 protected static TransactionTag getAncestorTransactionTag(YuzuTag tag)
121 {
122 return (TransactionTag)tag.getAncestorTag("com.micronova.jsp.tag.TransactionTag");
123 }
124
125 protected static TransactionTagSupport getAncestorTransactionTagSupport(YuzuTag tag)
126 {
127 return (TransactionTagSupport)tag.getAncestorTag("org.apache.taglibs.standard.tag.common.sql.TransactionTagSupport");
128 }
129
130
131
132 public static Connection getAncestorConnection(YuzuTag tag) throws Exception
133 {
134 TransactionTag transactionTag = getAncestorTransactionTag(tag);
135
136 if (transactionTag != null)
137 {
138 return transactionTag.getConnection();
139 }
140
141 TransactionTagSupport transactionTagSupport = getAncestorTransactionTagSupport(tag);
142
143 if (transactionTagSupport != null)
144 {
145 return transactionTagSupport.getSharedConnection();
146 }
147
148 return null;
149 }
150
151 protected void init()
152 {
153 super.init();
154
155 _dataSource = null;
156 _isolation = Connection.TRANSACTION_NONE;
157 _isolationBefore = Connection.TRANSACTION_NONE;
158 _connection = null;
159 _doesOwnConnection = false;
160 }
161
162 protected Connection getConnection(Object spec) throws Exception
163 {
164 Connection connection = _connection;
165
166 if (connection != null)
167 {
168 return connection;
169 }
170 else
171 {
172 if (spec == null)
173 {
174 spec = getConfiguration(Config.SQL_DATA_SOURCE, null);
175 }
176
177 connection = openConnection(spec);
178 }
179
180 return connection;
181 }
182
183 protected Connection getConnection() throws Exception
184 {
185 return getConnection(_dataSource);
186 }
187
188 public void initBody() throws Exception
189 {
190 Connection connection = null;
191
192 Object dataSource = _dataSource;
193
194 if (dataSource == null)
195 {
196 connection = getAncestorConnection(this);
197 }
198
199 if (connection != null)
200 {
201 _doesOwnConnection = false;
202 _connection = connection;
203 _isolationBefore = connection.getTransactionIsolation();
204 }
205 else
206 {
207 _doesOwnConnection = true;
208 connection = getConnection(dataSource);
209 connection.setAutoCommit(false);
210
211 _connection = connection;
212 }
213
214 if (connection != null)
215 {
216 int isolation = _isolation;
217
218 if (isolation != Connection.TRANSACTION_NONE)
219 {
220 connection.setTransactionIsolation(isolation);
221 }
222 }
223
224 super.initBody();
225 }
226
227 public void afterBody() throws Exception
228 {
229 super.afterBody();
230
231 if (_doesOwnConnection)
232 {
233 _connection.commit();
234 }
235 }
236
237 public void doCatch(Throwable t) throws Throwable
238 {
239 boolean doesOwnConnection = _doesOwnConnection;
240
241 if (doesOwnConnection)
242 {
243 _connection.rollback();
244 }
245
246 super.doCatch(t);
247 }
248
249 public void doFinally()
250 {
251 try
252 {
253 if (_doesOwnConnection)
254 {
255 try
256 {
257 _connection.close();
258 }
259 catch (Exception ee)
260 {
261 }
262 }
263 else
264 {
265 _connection.setTransactionIsolation(_isolationBefore);
266 }
267 }
268 catch (Exception e)
269 {
270 }
271
272 super.doFinally();
273 }
274
275 public void setDataSource(Object expression) throws Exception
276 {
277 Object dataSource = evaluateAttribute("dataSource", expression, Object .class);
278
279 if (!isEmptyString(dataSource))
280 {
281 _dataSource = dataSource;
282 }
283 }
284
285 public void setIsolation(Object expression) throws Exception
286 {
287 String isolationSpec = (String )evaluateAttribute("dataSource", expression, String .class);
288
289 if ("read_committed".equals(isolationSpec))
290 {
291 _isolation = Connection.TRANSACTION_READ_COMMITTED;
292 }
293 else if ("read_uncommitted".equals(isolationSpec))
294 {
295 _isolation = Connection.TRANSACTION_READ_UNCOMMITTED;
296 }
297 else if ("repeatable_read".equals(isolationSpec))
298 {
299 _isolation = Connection.TRANSACTION_REPEATABLE_READ;
300 }
301 else if ("serializable".equals(isolationSpec))
302 {
303 _isolation = Connection.TRANSACTION_SERIALIZABLE;
304 }
305 else if ("none".equals(isolationSpec))
306 {
307 _isolation = Connection.TRANSACTION_NONE;
308 }
309 else
310 {
311 throw new JspTagException("unsupported transaction isolation:" + isolationSpec);
312 }
313 }
314 }
315 |
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