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1 package org.apache.ojb.odmg;
2
3 import org.apache.commons.lang.SystemUtils;
4 import org.apache.ojb.broker.TestHelper;
5 import org.apache.ojb.junit.JUnitExtensions;
6 import org.odmg.Database;
7 import org.odmg.Implementation;
8 import org.odmg.LockNotGrantedException;
9 import org.odmg.Transaction;
10
11
19 public class LockingMultithreadedTest extends JUnitExtensions.MultiThreadedTestCase
20 {
21 private static int threadCount;
22 private static Implementation odmg;
23 private static Database db;
24 private final StringBuffer  result = new StringBuffer (2000);
25 private static final String eol = SystemUtils.LINE_SEPARATOR;
26 private final int concurrentThreads = 10;
28 private final int objectUpdates = 30;
30 private static final int maxAttempts = 100;
32 private static final int nearMax = (int) (maxAttempts * 0.75);
33
34
35 public static void main(String [] args)
36 {
37 String [] arr = {LockingMultithreadedTest.class.getName()};
38 junit.textui.TestRunner.main(arr);
39 }
40
41 public LockingMultithreadedTest(String s)
42 {
43 super(s);
44 }
45
46 protected void setUp() throws Exception
47 {
48 super.setUp();
49 }
50
51 protected void tearDown() throws Exception
52 {
53 super.tearDown();
54 }
55
56 public void testLockingOfObject() throws Exception
57 {
58
62 odmg = OJB.getInstance();
63 db = odmg.newDatabase();
64 db.open(TestHelper.DEF_DATABASE_NAME, Database.OPEN_READ_WRITE);
65
66 LockObject targetObject = createLockObjectWithRef();
67 storeObject(targetObject);
68
69 TestCaseRunnable tct [] = new TestCaseRunnable[concurrentThreads];
70 for (int i = 0; i < concurrentThreads; i++)
71 {
72
76 if (i % 2 == 0)
77 tct[i] = new LockHandle(targetObject);
78 else
79 tct[i] = new LockHandle(targetObject.makeCopy());
80 }
81 runTestCaseRunnables(tct);
83 System.out.println("*** Result of multithreaded lock test ***");
84 System.out.println(result.toString());
85 }
87
88 private LockObject createLockObjectWithRef()
89 {
90 int number = newThreadKey();
91 LockObject lo = new LockObject();
92 lo.setName("modified by thread: " + number);
93
94 LockObjectRef lor = new LockObjectRef();
95 lor.setName("modified by thread: " + number);
96
97 lo.setReference(lor);
98
99 return lo;
100 }
101
102 private void storeObject(Object obj) throws Exception
103 {
104 Transaction tx = odmg.newTransaction();
105
106 tx.begin();
107 tx.lock(obj, Transaction.WRITE);
108 tx.commit();
109 }
110
111 public static synchronized int newThreadKey()
112 {
113 return threadCount++;
114 }
115
116
120 class LockHandle extends JUnitExtensions.MultiThreadedTestCase.TestCaseRunnable
121 {
122 final LockObject obj;
123 int threadNumber;
124 private int counter = 0;
125
126 public LockHandle(LockObject obj)
127 {
128 super();
129 this.obj = obj;
130 }
131
132 public void runTestCase() throws Throwable
133 {
134 threadNumber = newThreadKey();
135 Transaction tx = odmg.newTransaction();
136 for (int i = 0; i < objectUpdates; i++)
137 {
138 tx.begin();
139 updateObject(tx, obj);
140 tx.commit();
141 counter = 0;
142 }
143 }
144
145 private void updateObject(final Transaction tx, final LockObject obj) throws Exception
146 {
147 try
148 {
149 tx.lock(obj, Transaction.WRITE);
150 tx.lock(obj.getReference(), Transaction.WRITE);
151 updateName(obj);
152 updateName(obj.getReference());
153 }
154 catch (LockNotGrantedException e)
155 {
156 if (counter < maxAttempts)
157 {
158 counter++;
159 if (counter > nearMax)
160 System.out.println("LockingMultithreadedTest: thread "
161 + threadNumber + " waits " + counter
162 + " times to update object. Maximal attempts before fail are " + maxAttempts
163 + ". This can be a result of low hardware.");
164 try
165 {
166 Thread.sleep(30);
167 }
168 catch(InterruptedException e1)
169 {
170 }
171 updateObject(tx, obj);
172 }
173 else
174 {
175 System.out.println("* Can't lock given object, will throw exception" +
176 " for thread number " + threadNumber + " *");
177 throw e;
178 }
179 }
180 }
181
182 private void updateName(LockObject obj)
183 {
184 if (obj.getName().length() < 100)
185 {
186 obj.setName(obj.getName() + "-" + threadNumber);
187 }
188 else
189 {
190 result.append(eol).append(obj.getName());
191 obj.setName("modified by thread: " + threadNumber);
192 }
193 }
194
195 private void updateName(LockObjectRef obj)
196 {
197 if (obj.getName().length() < 100)
198 {
199 obj.setName(obj.getName() + "-" + threadNumber);
200 }
201 else
202 {
203 obj.setName("modified by thread: " + threadNumber);
204 }
205 }
206 }
207
208 public static class LockObject
209 {
210 private Integer id;
211 private String name;
212 private Integer version;
213 private LockObjectRef reference;
214
215 public LockObject()
216 {
217 }
218
219 private LockObject(Integer id, String name, Integer version, LockObjectRef reference)
220 {
221 this.id = id;
222 this.name = name;
223 this.version = version;
224 this.reference = reference;
225 }
226
227 public LockObject makeCopy()
228 {
229 return new LockObject(id, name, version, reference != null ? reference.makeCopy() : null);
230 }
231
232 public Integer getId()
233 {
234 return id;
235 }
236
237 public void setId(Integer id)
238 {
239 this.id = id;
240 }
241
242 public String getName()
243 {
244 return name;
245 }
246
247 public void setName(String name)
248 {
249 this.name = name;
250 }
251
252 public Integer getVersion()
253 {
254 return version;
255 }
256
257 public void setVersion(Integer version)
258 {
259 this.version = version;
260 }
261
262 public LockObjectRef getReference()
263 {
264 return reference;
265 }
266
267 public void setReference(LockObjectRef reference)
268 {
269 this.reference = reference;
270 }
271 }
272
273 public static class LockObjectRef
274 {
275 private Integer id;
276 private String name;
277 private Integer version;
278
279 public LockObjectRef()
280 {
281 }
282
283 private LockObjectRef(Integer id, String name, Integer version)
284 {
285 this.id = id;
286 this.name = name;
287 this.version = version;
288 }
289
290 public LockObjectRef makeCopy()
291 {
292 return new LockObjectRef(id, name, version);
293 }
294
295 public Integer getId()
296 {
297 return id;
298 }
299
300 public void setId(Integer id)
301 {
302 this.id = id;
303 }
304
305 public String getName()
306 {
307 return name;
308 }
309
310 public void setName(String name)
311 {
312 this.name = name;
313 }
314
315 public Integer getVersion()
316 {
317 return version;
318 }
319
320 public void setVersion(Integer version)
321 {
322 this.version = version;
323 }
324 }
325 }
326 |
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