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1
8 package org.apache.avalon.excalibur.concurrent.test;
9
10 import junit.framework.TestCase;
11 import org.apache.avalon.excalibur.concurrent.ReadWriteLock;
12
13
18 public class ReadWriteLockTestCase
19 extends TestCase
20 {
21
26 static class TriesWriteLock
27 extends Thread 
28 {
29 protected ReadWriteLock m_lock;
30 protected boolean m_success = false;
31
32 public TriesWriteLock(ReadWriteLock lock)
33 {
34 m_lock = lock;
35 }
36
37 public boolean hasSuccess()
38 {
39 return m_success;
40 }
41
42 public void run ()
43 {
44 try
45 {
46 m_lock.aquireWrite();
47 m_success = true;
48 }
49 catch (Exception e)
50 {
51 }
54 }
55 }
56
57
62 static class TriesReadLock
63 extends Thread
64 {
65 protected ReadWriteLock m_lock;
66 protected boolean m_success = false;
67
68 public TriesReadLock( final ReadWriteLock lock )
69 {
70 m_lock = lock;
71 }
72
73 public boolean hasSuccess()
74 {
75 return m_success;
76 }
77
78 public void run ()
79 {
80 try
81 {
82 m_lock.aquireRead();
83 m_success = true;
84 }
85 catch( final Exception e )
86 {
87 }
90 }
91 }
92
93 public ReadWriteLockTestCase (String name) {
94 super (name);
95 }
96
97
101 public void testRWLock()
102 throws Exception
103 {
104 final ReadWriteLock lock = new ReadWriteLock();
105 final TriesWriteLock wl = new TriesWriteLock( lock );
106 final TriesReadLock rl = new TriesReadLock( lock );
107
108 rl.start ();
109 Thread.currentThread().sleep( 100 );
110 assertTrue( "Attempted to aquire read lock.", rl.hasSuccess () );
111
112 wl.start ();
113 Thread.currentThread().sleep( 100 );
114 assertTrue( "Attempted to aquire write lock.", !wl.hasSuccess () );
115
116 lock.release();
117
118 Thread.currentThread().sleep( 100 );
119 assertTrue( "Attempted to aquire write lock after releasing read lock.",
120 wl.hasSuccess () );
121
122 lock.release();
123
124 final TriesReadLock r2 = new TriesReadLock( lock );
128 r2.start ();
129 Thread.currentThread().sleep( 100 );
130 assertTrue( "Attempted to aquire read lock.", r2.hasSuccess () );
131
132 lock.release();
133 }
134
135
139 public void testIllegalState () throws Exception
140 {
141 ReadWriteLock lock = new ReadWriteLock();
142 try
143 {
144 lock.release();
145 fail( "ReadWriteLock did *not* signal illegal state when an attempt was made to release an unlocked lock." );
146 }
147 catch (IllegalStateException ise)
148 {
149 }
151 }
152
153
158 public void testMultipleWriters () throws Exception
159 {
160 ReadWriteLock lock = new ReadWriteLock();
161 TriesReadLock rla = new TriesReadLock( lock );
162 TriesReadLock rlb = new TriesReadLock( lock );
163 TriesWriteLock wla = new TriesWriteLock( lock );
164 TriesWriteLock wlb = new TriesWriteLock( lock );
165
166 rla.start ();
167 Thread.currentThread().sleep( 100 );
168 assertTrue( "Attempted to aquire read lock.", rla.hasSuccess () );
169
170 wla.start ();
171 wlb.start ();
172
173 Thread.currentThread().sleep( 100 );
178
179 rlb.start ();
180 Thread.currentThread().sleep( 100 );
181
182 assertTrue( "Attempted to aquire write lock, and succeeded even though it shouldn't be possible (rla has the lock).",
190 !wla.hasSuccess() && !wlb.hasSuccess() && !rlb.hasSuccess() );
191
192 lock.release();
197 Thread.currentThread().sleep( 100 );
198
199 assertTrue( "Attempted to aquire write lock after releasing read lock.",
207 (wla.hasSuccess () || wlb.hasSuccess () ) && !rlb.hasSuccess ()
208 && !(wla.hasSuccess () && wlb.hasSuccess () ));
209
210 lock.release();
214 Thread.currentThread().sleep( 100 );
215
216 assertTrue( "Attempted to aquire write lock after releasing read lock.",
223 wla.hasSuccess () && wlb.hasSuccess () && !rlb.hasSuccess () );
224
225 lock.release();
229 Thread.currentThread().sleep( 100 );
230 assertTrue( "Attempted to aquire write lock after releasing read lock.",
231 wla.hasSuccess () && wlb.hasSuccess () && rlb.hasSuccess () );
232 }
233
234
238 public void testMultipleReaders () throws Exception
239 {
240 ReadWriteLock lock = new ReadWriteLock();
241 TriesReadLock rla = new TriesReadLock( lock );
242 TriesReadLock rlb = new TriesReadLock( lock );
243 TriesWriteLock wla = new TriesWriteLock( lock );
244
245 rla.start ();
246 rlb.start ();
247 Thread.currentThread().sleep( 100 );
248 assertTrue( "Attempted to aquire read multiple read locks.",
249 rla.hasSuccess () && rlb.hasSuccess () );
250
251 wla.start ();
252 Thread.currentThread().sleep( 100 );
253 assertTrue( "Write lock aquired even though read locks are held.", !wla.hasSuccess () );
254
255 lock.release ();
256 Thread.currentThread().sleep( 100 );
257 assertTrue( "Write lock aquired even though read locks are held. (There should be one read lock left)",
258 !wla.hasSuccess () );
259
260 lock.release ();
261 Thread.currentThread().sleep( 100 );
262 assertTrue( "Write lock not aquired even though lock should be released.",
263 wla.hasSuccess () );
264 }
265
266
269 public void testTrying () throws Exception
270 {
271 ReadWriteLock lock = new ReadWriteLock();
272 TriesReadLock rla = new TriesReadLock( lock );
273 TriesReadLock rlb = new TriesReadLock( lock );
274 TriesWriteLock wla = new TriesWriteLock( lock );
275 TriesWriteLock wlb = new TriesWriteLock( lock );
276
277 rla.start ();
282 Thread.currentThread().sleep( 100 );
283 assertTrue( "Could not aquire a read lock.", rla.hasSuccess() );
284
285 assertTrue( "Could not aquire a read lock, even though only a read lock is held.",
286 lock.tryAquireRead() );
287
288 assertTrue( "Could aquire a write lock.", !lock.tryAquireWrite() );
289
290 lock.release();
294 lock.release();
295
296 assertTrue( "Could not aquire a write lock.", lock.tryAquireWrite() );
301 assertTrue( "Could aquire a read lock.", !lock.tryAquireRead() );
302 assertTrue( "Could aquire a write lock.", !lock.tryAquireWrite() );
303
304 lock.release();
308
309 assertTrue( "Could not aquire a write lock after releasing the lock.",
310 lock.tryAquireWrite() );
311 }
312
313
321 public void testDeadLock () throws Exception {
322 ReadWriteLock lock = new ReadWriteLock();
323 TriesReadLock rla = new TriesReadLock( lock );
324 TriesReadLock rlb = new TriesReadLock( lock );
325 TriesWriteLock wla = new TriesWriteLock( lock );
326 TriesWriteLock wlb = new TriesWriteLock( lock );
327
328 rla.start();
332 Thread.currentThread().sleep( 100 );
333 assertTrue( rla.hasSuccess() );
334
335 wla.start();
340 Thread.currentThread().sleep( 100 );
341 assertTrue( !wla.hasSuccess() );
342
343 wla.interrupt();
347
348 lock.release();
352
353 rlb.start();
360 Thread.currentThread().sleep( 100 );
361 assertTrue( rlb.hasSuccess() );
362 lock.release();
363
364 wlb.start();
365 Thread.currentThread().sleep( 100 );
366 assertTrue( wlb.hasSuccess() );
367 lock.release();
368 }
369 }
370
371
372 |
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