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root/jsr166/jsr166/src/test/tck/Collection8Test.java
Revision: 1.15
Committed: Sun Nov 6 04:15:45 2016 UTC (7 years, 6 months ago) by jsr166
Branch: MAIN
Changes since 1.14: +17 -2 lines
Log Message:
improve testNullPointerExceptions

File Contents

# Content
1 /*
2 * Written by Doug Lea and Martin Buchholz with assistance from
3 * members of JCP JSR-166 Expert Group and released to the public
4 * domain, as explained at
5 * http://creativecommons.org/publicdomain/zero/1.0/
6 */
7
8 import static java.util.concurrent.TimeUnit.MILLISECONDS;
9
10 import java.util.ArrayList;
11 import java.util.Collection;
12 import java.util.Collections;
13 import java.util.Deque;
14 import java.util.HashSet;
15 import java.util.Iterator;
16 import java.util.List;
17 import java.util.NoSuchElementException;
18 import java.util.Queue;
19 import java.util.Spliterator;
20 import java.util.concurrent.BlockingDeque;
21 import java.util.concurrent.BlockingQueue;
22 import java.util.concurrent.CountDownLatch;
23 import java.util.concurrent.Executors;
24 import java.util.concurrent.ExecutorService;
25 import java.util.concurrent.Future;
26 import java.util.concurrent.ThreadLocalRandom;
27 import java.util.concurrent.atomic.AtomicBoolean;
28 import java.util.concurrent.atomic.AtomicLong;
29 import java.util.concurrent.atomic.AtomicReference;
30 import java.util.function.Consumer;
31 import java.util.function.Predicate;
32
33 import junit.framework.Test;
34
35 /**
36 * Contains tests applicable to all jdk8+ Collection implementations.
37 * An extension of CollectionTest.
38 */
39 public class Collection8Test extends JSR166TestCase {
40 final CollectionImplementation impl;
41
42 /** Tests are parameterized by a Collection implementation. */
43 Collection8Test(CollectionImplementation impl, String methodName) {
44 super(methodName);
45 this.impl = impl;
46 }
47
48 public static Test testSuite(CollectionImplementation impl) {
49 return parameterizedTestSuite(Collection8Test.class,
50 CollectionImplementation.class,
51 impl);
52 }
53
54 Object bomb() {
55 return new Object() {
56 public boolean equals(Object x) { throw new AssertionError(); }
57 public int hashCode() { throw new AssertionError(); }
58 };
59 }
60
61 /** Checks properties of empty collections. */
62 public void testEmptyMeansEmpty() throws InterruptedException {
63 Collection c = impl.emptyCollection();
64 emptyMeansEmpty(c);
65
66 if (c instanceof java.io.Serializable)
67 emptyMeansEmpty(serialClone(c));
68
69 Collection clone = cloneableClone(c);
70 if (clone != null)
71 emptyMeansEmpty(clone);
72 }
73
74 void emptyMeansEmpty(Collection c) throws InterruptedException {
75 assertTrue(c.isEmpty());
76 assertEquals(0, c.size());
77 assertEquals("[]", c.toString());
78 {
79 Object[] a = c.toArray();
80 assertEquals(0, a.length);
81 assertSame(Object[].class, a.getClass());
82 }
83 {
84 Object[] a = new Object[0];
85 assertSame(a, c.toArray(a));
86 }
87 {
88 Integer[] a = new Integer[0];
89 assertSame(a, c.toArray(a));
90 }
91 {
92 Integer[] a = { 1, 2, 3};
93 assertSame(a, c.toArray(a));
94 assertNull(a[0]);
95 assertSame(2, a[1]);
96 assertSame(3, a[2]);
97 }
98 assertIteratorExhausted(c.iterator());
99 Consumer alwaysThrows = (e) -> { throw new AssertionError(); };
100 c.forEach(alwaysThrows);
101 c.iterator().forEachRemaining(alwaysThrows);
102 c.spliterator().forEachRemaining(alwaysThrows);
103 assertFalse(c.spliterator().tryAdvance(alwaysThrows));
104 if (c.spliterator().hasCharacteristics(Spliterator.SIZED))
105 assertEquals(0, c.spliterator().estimateSize());
106 assertFalse(c.contains(bomb()));
107 assertFalse(c.remove(bomb()));
108 if (c instanceof Queue) {
109 Queue q = (Queue) c;
110 assertNull(q.peek());
111 assertNull(q.poll());
112 }
113 if (c instanceof Deque) {
114 Deque d = (Deque) c;
115 assertNull(d.peekFirst());
116 assertNull(d.peekLast());
117 assertNull(d.pollFirst());
118 assertNull(d.pollLast());
119 assertIteratorExhausted(d.descendingIterator());
120 d.descendingIterator().forEachRemaining(alwaysThrows);
121 assertFalse(d.removeFirstOccurrence(bomb()));
122 assertFalse(d.removeLastOccurrence(bomb()));
123 }
124 if (c instanceof BlockingQueue) {
125 BlockingQueue q = (BlockingQueue) c;
126 assertNull(q.poll(0L, MILLISECONDS));
127 }
128 if (c instanceof BlockingDeque) {
129 BlockingDeque q = (BlockingDeque) c;
130 assertNull(q.pollFirst(0L, MILLISECONDS));
131 assertNull(q.pollLast(0L, MILLISECONDS));
132 }
133 }
134
135 public void testNullPointerExceptions() throws InterruptedException {
136 Collection c = impl.emptyCollection();
137 assertThrows(
138 NullPointerException.class,
139 () -> c.addAll(null),
140 () -> c.containsAll(null),
141 () -> c.retainAll(null),
142 () -> c.removeAll(null),
143 () -> c.removeIf(null),
144 () -> c.forEach(null),
145 () -> c.iterator().forEachRemaining(null),
146 () -> c.spliterator().forEachRemaining(null),
147 () -> c.spliterator().tryAdvance(null),
148 () -> c.toArray(null));
149
150 if (!impl.permitsNulls()) {
151 assertThrows(
152 NullPointerException.class,
153 () -> c.add(null));
154 }
155 if (!impl.permitsNulls() && c instanceof Queue) {
156 Queue q = (Queue) c;
157 assertThrows(
158 NullPointerException.class,
159 () -> q.offer(null));
160 }
161 if (!impl.permitsNulls() && c instanceof Deque) {
162 Deque d = (Deque) c;
163 assertThrows(
164 NullPointerException.class,
165 () -> d.addFirst(null),
166 () -> d.addLast(null),
167 () -> d.offerFirst(null),
168 () -> d.offerLast(null),
169 () -> d.push(null),
170 () -> d.descendingIterator().forEachRemaining(null));
171 }
172 if (c instanceof BlockingQueue) {
173 BlockingQueue q = (BlockingQueue) c;
174 assertThrows(
175 NullPointerException.class,
176 () -> {
177 try { q.offer(null, 1L, MILLISECONDS); }
178 catch (InterruptedException ex) {
179 throw new AssertionError(ex);
180 }},
181 () -> {
182 try { q.put(null); }
183 catch (InterruptedException ex) {
184 throw new AssertionError(ex);
185 }});
186 }
187 if (c instanceof BlockingDeque) {
188 BlockingDeque q = (BlockingDeque) c;
189 assertThrows(
190 NullPointerException.class,
191 () -> {
192 try { q.offerFirst(null, 1L, MILLISECONDS); }
193 catch (InterruptedException ex) {
194 throw new AssertionError(ex);
195 }},
196 () -> {
197 try { q.offerLast(null, 1L, MILLISECONDS); }
198 catch (InterruptedException ex) {
199 throw new AssertionError(ex);
200 }},
201 () -> {
202 try { q.putFirst(null); }
203 catch (InterruptedException ex) {
204 throw new AssertionError(ex);
205 }},
206 () -> {
207 try { q.putLast(null); }
208 catch (InterruptedException ex) {
209 throw new AssertionError(ex);
210 }});
211 }
212 }
213
214 public void testNoSuchElementExceptions() {
215 Collection c = impl.emptyCollection();
216 assertThrows(
217 NoSuchElementException.class,
218 () -> c.iterator().next());
219
220 if (c instanceof Queue) {
221 Queue q = (Queue) c;
222 assertThrows(
223 NoSuchElementException.class,
224 () -> q.element(),
225 () -> q.remove());
226 }
227 if (c instanceof Deque) {
228 Deque d = (Deque) c;
229 assertThrows(
230 NoSuchElementException.class,
231 () -> d.getFirst(),
232 () -> d.getLast(),
233 () -> d.removeFirst(),
234 () -> d.removeLast(),
235 () -> d.pop(),
236 () -> d.descendingIterator().next());
237 }
238 }
239
240 public void testRemoveIf() {
241 Collection c = impl.emptyCollection();
242 ThreadLocalRandom rnd = ThreadLocalRandom.current();
243 int n = rnd.nextInt(6);
244 for (int i = 0; i < n; i++) c.add(impl.makeElement(i));
245 AtomicReference threwAt = new AtomicReference(null);
246 ArrayList survivors = new ArrayList(c);
247 ArrayList accepts = new ArrayList();
248 ArrayList rejects = new ArrayList();
249 Predicate randomPredicate = (e) -> {
250 assertNull(threwAt.get());
251 switch (rnd.nextInt(3)) {
252 case 0: accepts.add(e); return true;
253 case 1: rejects.add(e); return false;
254 case 2: threwAt.set(e); throw new ArithmeticException();
255 default: throw new AssertionError();
256 }
257 };
258 try {
259 assertFalse(survivors.contains(null));
260 try {
261 boolean modified = c.removeIf(randomPredicate);
262 if (!modified) {
263 assertNull(threwAt.get());
264 assertEquals(n, rejects.size());
265 assertEquals(0, accepts.size());
266 }
267 } catch (ArithmeticException ok) {}
268 survivors.removeAll(accepts);
269 assertEquals(n - accepts.size(), c.size());
270 assertTrue(c.containsAll(survivors));
271 assertTrue(survivors.containsAll(rejects));
272 for (Object x : accepts) assertFalse(c.contains(x));
273 if (threwAt.get() == null)
274 assertEquals(accepts.size() + rejects.size(), n);
275 } catch (Throwable ex) {
276 System.err.println(impl.klazz());
277 System.err.printf("c=%s%n", c);
278 System.err.printf("n=%d%n", n);
279 System.err.printf("accepts=%s%n", accepts);
280 System.err.printf("rejects=%s%n", rejects);
281 System.err.printf("survivors=%s%n", survivors);
282 System.err.printf("threw=%s%n", threwAt.get());
283 throw ex;
284 }
285 }
286
287 /**
288 * Various ways of traversing a collection yield same elements
289 */
290 public void testIteratorEquivalence() {
291 Collection c = impl.emptyCollection();
292 ThreadLocalRandom rnd = ThreadLocalRandom.current();
293 int n = rnd.nextInt(6);
294 for (int i = 0; i < n; i++) c.add(impl.makeElement(i));
295 ArrayList iterated = new ArrayList();
296 ArrayList iteratedForEachRemaining = new ArrayList();
297 ArrayList tryAdvanced = new ArrayList();
298 ArrayList spliterated = new ArrayList();
299 ArrayList forEached = new ArrayList();
300 ArrayList removeIfed = new ArrayList();
301 for (Object x : c) iterated.add(x);
302 c.iterator().forEachRemaining(e -> iteratedForEachRemaining.add(e));
303 for (Spliterator s = c.spliterator();
304 s.tryAdvance(e -> tryAdvanced.add(e)); ) {}
305 c.spliterator().forEachRemaining(e -> spliterated.add(e));
306 c.forEach(e -> forEached.add(e));
307 c.removeIf(e -> { removeIfed.add(e); return false; });
308 boolean ordered =
309 c.spliterator().hasCharacteristics(Spliterator.ORDERED);
310 if (c instanceof List || c instanceof Deque)
311 assertTrue(ordered);
312 if (ordered) {
313 assertEquals(iterated, iteratedForEachRemaining);
314 assertEquals(iterated, tryAdvanced);
315 assertEquals(iterated, spliterated);
316 assertEquals(iterated, forEached);
317 assertEquals(iterated, removeIfed);
318 } else {
319 HashSet cset = new HashSet(c);
320 assertEquals(cset, new HashSet(iterated));
321 assertEquals(cset, new HashSet(iteratedForEachRemaining));
322 assertEquals(cset, new HashSet(tryAdvanced));
323 assertEquals(cset, new HashSet(spliterated));
324 assertEquals(cset, new HashSet(forEached));
325 assertEquals(cset, new HashSet(removeIfed));
326 }
327 if (c instanceof Deque) {
328 Deque d = (Deque) c;
329 ArrayList descending = new ArrayList();
330 ArrayList descendingForEachRemaining = new ArrayList();
331 for (Iterator it = d.descendingIterator(); it.hasNext(); )
332 descending.add(it.next());
333 d.descendingIterator().forEachRemaining(
334 e -> descendingForEachRemaining.add(e));
335 Collections.reverse(descending);
336 Collections.reverse(descendingForEachRemaining);
337 assertEquals(iterated, descending);
338 assertEquals(iterated, descendingForEachRemaining);
339 }
340 }
341
342 /**
343 * Calling Iterator#remove() after Iterator#forEachRemaining
344 * should remove last element
345 */
346 public void testRemoveAfterForEachRemaining() {
347 Collection c = impl.emptyCollection();
348 ThreadLocalRandom rnd = ThreadLocalRandom.current();
349 {
350 int n = 3 + rnd.nextInt(2);
351 for (int i = 0; i < n; i++) c.add(impl.makeElement(i));
352 Iterator it = c.iterator();
353 assertTrue(it.hasNext());
354 assertEquals(impl.makeElement(0), it.next());
355 assertTrue(it.hasNext());
356 assertEquals(impl.makeElement(1), it.next());
357 it.forEachRemaining((e) -> {});
358 it.remove();
359 assertEquals(n - 1, c.size());
360 for (int i = 0; i < n - 1; i++)
361 assertTrue(c.contains(impl.makeElement(i)));
362 assertFalse(c.contains(impl.makeElement(n - 1)));
363 }
364 if (c instanceof Deque) {
365 Deque d = (Deque) impl.emptyCollection();
366 int n = 3 + rnd.nextInt(2);
367 for (int i = 0; i < n; i++) d.add(impl.makeElement(i));
368 Iterator it = d.descendingIterator();
369 assertTrue(it.hasNext());
370 assertEquals(impl.makeElement(n - 1), it.next());
371 assertTrue(it.hasNext());
372 assertEquals(impl.makeElement(n - 2), it.next());
373 it.forEachRemaining((e) -> {});
374 it.remove();
375 assertEquals(n - 1, d.size());
376 for (int i = 1; i < n; i++)
377 assertTrue(d.contains(impl.makeElement(i)));
378 assertFalse(d.contains(impl.makeElement(0)));
379 }
380 }
381
382 /**
383 * stream().forEach returns elements in the collection
384 */
385 public void testStreamForEach() throws Throwable {
386 final Collection c = impl.emptyCollection();
387 final AtomicLong count = new AtomicLong(0L);
388 final Object x = impl.makeElement(1);
389 final Object y = impl.makeElement(2);
390 final ArrayList found = new ArrayList();
391 Consumer<Object> spy = (o) -> { found.add(o); };
392 c.stream().forEach(spy);
393 assertTrue(found.isEmpty());
394
395 assertTrue(c.add(x));
396 c.stream().forEach(spy);
397 assertEquals(Collections.singletonList(x), found);
398 found.clear();
399
400 assertTrue(c.add(y));
401 c.stream().forEach(spy);
402 assertEquals(2, found.size());
403 assertTrue(found.contains(x));
404 assertTrue(found.contains(y));
405 found.clear();
406
407 c.clear();
408 c.stream().forEach(spy);
409 assertTrue(found.isEmpty());
410 }
411
412 public void testStreamForEachConcurrentStressTest() throws Throwable {
413 if (!impl.isConcurrent()) return;
414 final Collection c = impl.emptyCollection();
415 final long testDurationMillis = timeoutMillis();
416 final AtomicBoolean done = new AtomicBoolean(false);
417 final Object elt = impl.makeElement(1);
418 final Future<?> f1, f2;
419 final ExecutorService pool = Executors.newCachedThreadPool();
420 try (PoolCleaner cleaner = cleaner(pool, done)) {
421 final CountDownLatch threadsStarted = new CountDownLatch(2);
422 Runnable checkElt = () -> {
423 threadsStarted.countDown();
424 while (!done.get())
425 c.stream().forEach((x) -> { assertSame(x, elt); }); };
426 Runnable addRemove = () -> {
427 threadsStarted.countDown();
428 while (!done.get()) {
429 assertTrue(c.add(elt));
430 assertTrue(c.remove(elt));
431 }};
432 f1 = pool.submit(checkElt);
433 f2 = pool.submit(addRemove);
434 Thread.sleep(testDurationMillis);
435 }
436 assertNull(f1.get(0L, MILLISECONDS));
437 assertNull(f2.get(0L, MILLISECONDS));
438 }
439
440 /**
441 * collection.forEach returns elements in the collection
442 */
443 public void testForEach() throws Throwable {
444 final Collection c = impl.emptyCollection();
445 final AtomicLong count = new AtomicLong(0L);
446 final Object x = impl.makeElement(1);
447 final Object y = impl.makeElement(2);
448 final ArrayList found = new ArrayList();
449 Consumer<Object> spy = (o) -> { found.add(o); };
450 c.forEach(spy);
451 assertTrue(found.isEmpty());
452
453 assertTrue(c.add(x));
454 c.forEach(spy);
455 assertEquals(Collections.singletonList(x), found);
456 found.clear();
457
458 assertTrue(c.add(y));
459 c.forEach(spy);
460 assertEquals(2, found.size());
461 assertTrue(found.contains(x));
462 assertTrue(found.contains(y));
463 found.clear();
464
465 c.clear();
466 c.forEach(spy);
467 assertTrue(found.isEmpty());
468 }
469
470 public void testForEachConcurrentStressTest() throws Throwable {
471 if (!impl.isConcurrent()) return;
472 final Collection c = impl.emptyCollection();
473 final long testDurationMillis = timeoutMillis();
474 final AtomicBoolean done = new AtomicBoolean(false);
475 final Object elt = impl.makeElement(1);
476 final Future<?> f1, f2;
477 final ExecutorService pool = Executors.newCachedThreadPool();
478 try (PoolCleaner cleaner = cleaner(pool, done)) {
479 final CountDownLatch threadsStarted = new CountDownLatch(2);
480 Runnable checkElt = () -> {
481 threadsStarted.countDown();
482 while (!done.get())
483 c.forEach((x) -> { assertSame(x, elt); }); };
484 Runnable addRemove = () -> {
485 threadsStarted.countDown();
486 while (!done.get()) {
487 assertTrue(c.add(elt));
488 assertTrue(c.remove(elt));
489 }};
490 f1 = pool.submit(checkElt);
491 f2 = pool.submit(addRemove);
492 Thread.sleep(testDurationMillis);
493 }
494 assertNull(f1.get(0L, MILLISECONDS));
495 assertNull(f2.get(0L, MILLISECONDS));
496 }
497
498 // public void testCollection8DebugFail() {
499 // fail(impl.klazz().getSimpleName());
500 // }
501 }