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1
64
65 package com.jcorporate.expresso.core.dbobj;
66
67 import EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap;
68 import com.jcorporate.expresso.core.dataobjects.DataFieldMetaData;
69 import com.jcorporate.expresso.core.dataobjects.jdbc.JDBCObjectMetaData;
70 import com.jcorporate.expresso.core.db.DBException;
71 import com.jcorporate.expresso.core.misc.ConfigManager;
72 import com.jcorporate.expresso.core.misc.ReusableLong;
73
74 import java.util.Enumeration  ;
75 import java.util.Iterator ;
76
77
78
89 public class NextNumberImpl
90 extends NextNumber {
91
92
99 protected volatile ConcurrentReaderHashMap contextMap = new ConcurrentReaderHashMap();
100
101 private Object mInitLock = new Object ();
102
103
106 public NextNumberImpl() {
107 for (Enumeration e = ConfigManager.getAllConfigKeys(); e.hasMoreElements();) {
108 String configKey = (String ) e.nextElement();
109 contextMap.put(configKey, new ConcurrentReaderHashMap(40));
110 }
111 }
112
113
121 public void initialize(String db, DBObject callingObject)
122 throws DBException {
123 callingObject.setDataContext(db);
124
125 Iterator i = callingObject.getMetaData().getAllFieldsMap().values().iterator();
126 while (i.hasNext()) {
127 DBField dbf = (DBField) i.next();
128
129 if (dbf.isAutoIncremented()) {
130 String fieldName = dbf.getName();
131 registerField(db, callingObject, fieldName);
133 }
134
135 }
136 }
137
138
141 public void registerField(String db, DBObject callingDBOBject,
142 String fieldName)
143 throws DBException {
144 String hashKey = getKey(callingDBOBject, fieldName);
145 ConcurrentReaderHashMap nextNumMap = (ConcurrentReaderHashMap) contextMap.get(db);
146
147 if (nextNumMap == null) {
148 throw new DBException("Uninitialized nextnumber context map");
149 }
150 if (!nextNumMap.containsKey(hashKey)) {
151
152 long l = getMax(db, callingDBOBject, fieldName);
154 long setValue = 0;
155 boolean didInit = false;
156
157 synchronized (nextNumMap) {
161 if (!nextNumMap.containsKey(hashKey)) {
163 nextNumMap.put(hashKey, new ReusableLong(l));
164 setValue = ((ReusableLong) nextNumMap.get(hashKey)).longValue();
166 didInit = true;
167 }
168 }
169
170 if (didInit && log.isDebugEnabled()) {
171 log.debug("initialized hash entry for key: "
172 + hashKey + " to value: " + l
173 + " and confirmed value: " + setValue);
174 }
175
176 }
177 }
178
179
191 private ReusableLong getNextNumberObject(String db,
192 DBObject callingDBObject,
193 String fieldName)
194 throws DBException {
195 String key = getKey(callingDBObject, fieldName);
196 ConcurrentReaderHashMap myDBMap = (ConcurrentReaderHashMap) contextMap.get(db);
197 ReusableLong rl = (ReusableLong) myDBMap.get(key);
198
199 if (rl == null) {
200 synchronized (mInitLock) {
205 if (myDBMap.get(key) == null) {
207 initialize(db, callingDBObject);
208 }
209 }
210
211 rl = (ReusableLong) myDBMap.get(key);
212
213 if (rl == null) {
214 DataFieldMetaData meta = callingDBObject.getFieldMetaData(fieldName);
217 if (!meta.isAutoIncremented() && log.isDebugEnabled()) {
218 log.debug("NextNumber.getNext() called for table.field, '"
219 + ((JDBCObjectMetaData) callingDBObject.getMetaData()).getTargetSQLTable(
220 callingDBObject.getDataContext())
221 + "." + fieldName
222 + "', which is not auto-incrementing type. Setting up hash entry anyway.");
223 }
224 registerField(db, callingDBObject, fieldName);
225 rl = (ReusableLong) myDBMap.get(key);
226 }
227
228 if (rl == null) {
229 throw new DBException("Unable to locate nextnumber entry for key: " + key);
230 }
231 }
232
233 return rl;
234 }
235
236
244 protected void checkParams(String db,
245 DBObject callingObject,
246 String fieldName)
247 throws DBException {
248
249 if (db == null || db.length() == 0) {
250 throw new DBException("NextNumber parameter 'db' must not be null or zero length");
251 }
252 if (callingObject == null) {
253 throw new DBException("NextNumber parameter 'callingDBOBject' must not be null");
254 }
255 if (fieldName == null) {
256 throw new DBException("NextNumber parameter 'fieldName' must not be null");
257 }
258
259 if (contextMap.get(db) == null) {
260 throw new DBException("NextNumber Unable to locate nextnumber map for context " + db);
261 }
262
263 }
264
265
268 public long getNext(String db, DBObject callingDBObject, String fieldName)
269 throws DBException {
270
271 if (CHECK_PARAMETERS) {
272 checkParams(db,
273 callingDBObject,
274 fieldName);
275 }
276
277
278 ReusableLong theNextNumberObject = getNextNumberObject(db,
279 callingDBObject,
280 fieldName);
281
282
283 long result;
284
285 synchronized (theNextNumberObject) {
289 result = theNextNumberObject.longValue();
290 result++;
291 theNextNumberObject.setLong(result);
292 }
293
294 if (log.isDebugEnabled()) {
295 log.debug("getNext returns, for hash key: "
296 + getKey(callingDBObject, fieldName) + " the value: " + result);
297 }
298
299
300 return result;
301 }
302
303
309 public void reset(String db) {
310 ConcurrentReaderHashMap myDBMap = (ConcurrentReaderHashMap) contextMap.get(db);
311
312 if (myDBMap != null) {
313 synchronized (myDBMap) {
317 myDBMap.clear();
318 }
319 }
320 }
321
322
329 public void reset(String db, DBObject callingObject) {
330 ConcurrentReaderHashMap myDBMap = (ConcurrentReaderHashMap) contextMap.get(db);
331
332 try {
333 if (myDBMap != null) {
334 Iterator i = callingObject.getMetaData().getAllFieldsMap().values().iterator();
335
336 while (i.hasNext()) {
337 DBField dbf = (DBField) i.next();
338
339 if (dbf.isAutoIncremented()) {
340 String fieldName = dbf.getName();
341 String hashKey = getKey(callingObject, fieldName);
342
343 if (myDBMap.containsKey(hashKey)) {
344
345 synchronized (myDBMap) {
349 if (myDBMap.containsKey(hashKey)) {
351 myDBMap.remove(hashKey);
352 }
353 }
354
355 }
356
357 }
358
359 }
360 }
361 } catch (DBException dbe) {
362 log.error("Error clearing one dbobject for next number, clearing whole stack");
363
364 if (myDBMap != null) {
365 synchronized (myDBMap) {
366 myDBMap.clear();
367 }
368 }
369 }
370 }
371 }
372 |
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