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/* |
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* Written by Doug Lea and Martin Buchholz with assistance from |
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* members of JCP JSR-166 Expert Group and released to the public |
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* domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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import static java.util.concurrent.TimeUnit.HOURS; |
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import static java.util.concurrent.TimeUnit.MILLISECONDS; |
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|
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import java.util.ArrayList; |
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import java.util.Arrays; |
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import java.util.Collection; |
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import java.util.Collections; |
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import java.util.Deque; |
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import java.util.HashSet; |
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import java.util.Iterator; |
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import java.util.List; |
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import java.util.NoSuchElementException; |
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import java.util.Queue; |
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import java.util.Spliterator; |
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import java.util.concurrent.BlockingDeque; |
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import java.util.concurrent.BlockingQueue; |
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import java.util.concurrent.CountDownLatch; |
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import java.util.concurrent.Executors; |
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import java.util.concurrent.ExecutorService; |
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import java.util.concurrent.Future; |
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import java.util.concurrent.Phaser; |
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import java.util.concurrent.ThreadLocalRandom; |
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import java.util.concurrent.atomic.AtomicBoolean; |
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import java.util.concurrent.atomic.AtomicLong; |
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import java.util.concurrent.atomic.AtomicReference; |
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import java.util.function.Consumer; |
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import java.util.function.Predicate; |
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import java.util.stream.Collectors; |
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|
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import junit.framework.Test; |
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|
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/** |
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* Contains tests applicable to all jdk8+ Collection implementations. |
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* An extension of CollectionTest. |
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*/ |
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public class Collection8Test extends JSR166TestCase { |
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final CollectionImplementation impl; |
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|
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/** Tests are parameterized by a Collection implementation. */ |
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Collection8Test(CollectionImplementation impl, String methodName) { |
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super(methodName); |
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this.impl = impl; |
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} |
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|
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public static Test testSuite(CollectionImplementation impl) { |
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return parameterizedTestSuite(Collection8Test.class, |
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CollectionImplementation.class, |
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impl); |
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} |
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|
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Object bomb() { |
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return new Object() { |
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public boolean equals(Object x) { throw new AssertionError(); } |
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public int hashCode() { throw new AssertionError(); } |
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}; |
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} |
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|
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/** Checks properties of empty collections. */ |
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public void testEmptyMeansEmpty() throws Throwable { |
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Collection c = impl.emptyCollection(); |
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emptyMeansEmpty(c); |
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|
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if (c instanceof java.io.Serializable) { |
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try { |
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emptyMeansEmpty(serialClonePossiblyFailing(c)); |
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} catch (java.io.NotSerializableException ex) { |
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// excusable when we have a serializable wrapper around |
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// a non-serializable collection, as can happen with: |
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// Vector.subList() => wrapped AbstractList$RandomAccessSubList |
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if (testImplementationDetails |
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&& (! c.getClass().getName().matches( |
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"java.util.Collections.*"))) |
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throw ex; |
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} |
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} |
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|
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Collection clone = cloneableClone(c); |
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if (clone != null) |
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emptyMeansEmpty(clone); |
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} |
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|
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void emptyMeansEmpty(Collection c) throws InterruptedException { |
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assertTrue(c.isEmpty()); |
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assertEquals(0, c.size()); |
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assertEquals("[]", c.toString()); |
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{ |
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Object[] a = c.toArray(); |
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assertEquals(0, a.length); |
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assertSame(Object[].class, a.getClass()); |
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} |
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{ |
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Object[] a = new Object[0]; |
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assertSame(a, c.toArray(a)); |
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} |
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{ |
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Integer[] a = new Integer[0]; |
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assertSame(a, c.toArray(a)); |
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} |
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{ |
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Integer[] a = { 1, 2, 3}; |
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assertSame(a, c.toArray(a)); |
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assertNull(a[0]); |
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assertSame(2, a[1]); |
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assertSame(3, a[2]); |
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} |
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assertIteratorExhausted(c.iterator()); |
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Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
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c.forEach(alwaysThrows); |
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c.iterator().forEachRemaining(alwaysThrows); |
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c.spliterator().forEachRemaining(alwaysThrows); |
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assertFalse(c.spliterator().tryAdvance(alwaysThrows)); |
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if (c.spliterator().hasCharacteristics(Spliterator.SIZED)) |
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assertEquals(0, c.spliterator().estimateSize()); |
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assertFalse(c.contains(bomb())); |
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assertFalse(c.remove(bomb())); |
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if (c instanceof Queue) { |
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Queue q = (Queue) c; |
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assertNull(q.peek()); |
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assertNull(q.poll()); |
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} |
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if (c instanceof Deque) { |
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Deque d = (Deque) c; |
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assertNull(d.peekFirst()); |
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assertNull(d.peekLast()); |
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assertNull(d.pollFirst()); |
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assertNull(d.pollLast()); |
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assertIteratorExhausted(d.descendingIterator()); |
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d.descendingIterator().forEachRemaining(alwaysThrows); |
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assertFalse(d.removeFirstOccurrence(bomb())); |
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assertFalse(d.removeLastOccurrence(bomb())); |
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} |
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if (c instanceof BlockingQueue) { |
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BlockingQueue q = (BlockingQueue) c; |
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assertNull(q.poll(0L, MILLISECONDS)); |
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} |
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if (c instanceof BlockingDeque) { |
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BlockingDeque q = (BlockingDeque) c; |
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assertNull(q.pollFirst(0L, MILLISECONDS)); |
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assertNull(q.pollLast(0L, MILLISECONDS)); |
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} |
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} |
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|
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public void testNullPointerExceptions() throws InterruptedException { |
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Collection c = impl.emptyCollection(); |
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assertThrows( |
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NullPointerException.class, |
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() -> c.addAll(null), |
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() -> c.containsAll(null), |
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() -> c.retainAll(null), |
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() -> c.removeAll(null), |
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() -> c.removeIf(null), |
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() -> c.forEach(null), |
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() -> c.iterator().forEachRemaining(null), |
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() -> c.spliterator().forEachRemaining(null), |
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() -> c.spliterator().tryAdvance(null), |
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() -> c.toArray(null)); |
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|
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if (!impl.permitsNulls()) { |
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assertThrows( |
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NullPointerException.class, |
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() -> c.add(null)); |
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} |
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if (!impl.permitsNulls() && c instanceof Queue) { |
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Queue q = (Queue) c; |
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assertThrows( |
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NullPointerException.class, |
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() -> q.offer(null)); |
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} |
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if (!impl.permitsNulls() && c instanceof Deque) { |
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Deque d = (Deque) c; |
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assertThrows( |
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NullPointerException.class, |
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() -> d.addFirst(null), |
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() -> d.addLast(null), |
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() -> d.offerFirst(null), |
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() -> d.offerLast(null), |
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() -> d.push(null), |
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() -> d.descendingIterator().forEachRemaining(null)); |
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} |
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if (c instanceof BlockingQueue) { |
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BlockingQueue q = (BlockingQueue) c; |
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assertThrows( |
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NullPointerException.class, |
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() -> { |
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try { q.offer(null, 1L, HOURS); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}, |
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() -> { |
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try { q.put(null); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}); |
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} |
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if (c instanceof BlockingDeque) { |
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BlockingDeque q = (BlockingDeque) c; |
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assertThrows( |
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NullPointerException.class, |
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() -> { |
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try { q.offerFirst(null, 1L, HOURS); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}, |
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() -> { |
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try { q.offerLast(null, 1L, HOURS); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}, |
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() -> { |
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try { q.putFirst(null); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}, |
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() -> { |
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try { q.putLast(null); } |
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catch (InterruptedException ex) { |
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throw new AssertionError(ex); |
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}}); |
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} |
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} |
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|
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public void testNoSuchElementExceptions() { |
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Collection c = impl.emptyCollection(); |
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assertThrows( |
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NoSuchElementException.class, |
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() -> c.iterator().next()); |
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|
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if (c instanceof Queue) { |
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Queue q = (Queue) c; |
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assertThrows( |
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NoSuchElementException.class, |
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() -> q.element(), |
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() -> q.remove()); |
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} |
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if (c instanceof Deque) { |
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Deque d = (Deque) c; |
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assertThrows( |
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NoSuchElementException.class, |
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() -> d.getFirst(), |
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() -> d.getLast(), |
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() -> d.removeFirst(), |
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() -> d.removeLast(), |
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() -> d.pop(), |
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() -> d.descendingIterator().next()); |
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} |
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} |
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|
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public void testRemoveIf() { |
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Collection c = impl.emptyCollection(); |
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boolean ordered = |
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c.spliterator().hasCharacteristics(Spliterator.ORDERED); |
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ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
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int n = rnd.nextInt(6); |
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for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
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AtomicReference threwAt = new AtomicReference(null); |
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List orig = rnd.nextBoolean() |
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? new ArrayList(c) |
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: Arrays.asList(c.toArray()); |
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|
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// Merely creating an iterator can change ArrayBlockingQueue behavior |
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Iterator it = rnd.nextBoolean() ? c.iterator() : null; |
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|
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ArrayList survivors = new ArrayList(); |
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ArrayList accepts = new ArrayList(); |
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ArrayList rejects = new ArrayList(); |
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|
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Predicate randomPredicate = e -> { |
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assertNull(threwAt.get()); |
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switch (rnd.nextInt(3)) { |
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case 0: accepts.add(e); return true; |
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case 1: rejects.add(e); return false; |
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case 2: threwAt.set(e); throw new ArithmeticException(); |
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default: throw new AssertionError(); |
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} |
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}; |
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try { |
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try { |
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boolean modified = c.removeIf(randomPredicate); |
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assertNull(threwAt.get()); |
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assertEquals(modified, accepts.size() > 0); |
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assertEquals(modified, rejects.size() != n); |
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assertEquals(accepts.size() + rejects.size(), n); |
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if (ordered) { |
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assertEquals(rejects, |
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Arrays.asList(c.toArray())); |
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} else { |
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assertEquals(new HashSet(rejects), |
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new HashSet(Arrays.asList(c.toArray()))); |
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} |
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} catch (ArithmeticException ok) { |
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assertNotNull(threwAt.get()); |
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assertTrue(c.contains(threwAt.get())); |
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} |
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if (it != null && impl.isConcurrent()) |
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// check for weakly consistent iterator |
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while (it.hasNext()) assertTrue(orig.contains(it.next())); |
| 304 |
switch (rnd.nextInt(4)) { |
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case 0: survivors.addAll(c); break; |
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case 1: survivors.addAll(Arrays.asList(c.toArray())); break; |
| 307 |
case 2: c.forEach(survivors::add); break; |
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case 3: for (Object e : c) survivors.add(e); break; |
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} |
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assertTrue(orig.containsAll(accepts)); |
| 311 |
assertTrue(orig.containsAll(rejects)); |
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assertTrue(orig.containsAll(survivors)); |
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assertTrue(orig.containsAll(c)); |
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assertTrue(c.containsAll(rejects)); |
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assertTrue(c.containsAll(survivors)); |
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assertTrue(survivors.containsAll(rejects)); |
| 317 |
if (threwAt.get() == null) { |
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assertEquals(n - accepts.size(), c.size()); |
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for (Object x : accepts) assertFalse(c.contains(x)); |
| 320 |
} else { |
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// Two acceptable behaviors: entire removeIf call is one |
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// transaction, or each element processed is one transaction. |
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assertTrue(n == c.size() || n == c.size() + accepts.size()); |
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int k = 0; |
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for (Object x : accepts) if (c.contains(x)) k++; |
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assertTrue(k == accepts.size() || k == 0); |
| 327 |
} |
| 328 |
} catch (Throwable ex) { |
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System.err.println(impl.klazz()); |
| 330 |
// c is at risk of corruption if we got here, so be lenient |
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try { System.err.printf("c=%s%n", c); } |
| 332 |
catch (Throwable t) { t.printStackTrace(); } |
| 333 |
System.err.printf("n=%d%n", n); |
| 334 |
System.err.printf("orig=%s%n", orig); |
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System.err.printf("accepts=%s%n", accepts); |
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System.err.printf("rejects=%s%n", rejects); |
| 337 |
System.err.printf("survivors=%s%n", survivors); |
| 338 |
System.err.printf("threwAt=%s%n", threwAt.get()); |
| 339 |
throw ex; |
| 340 |
} |
| 341 |
} |
| 342 |
|
| 343 |
/** |
| 344 |
* Various ways of traversing a collection yield same elements |
| 345 |
*/ |
| 346 |
public void testIteratorEquivalence() { |
| 347 |
Collection c = impl.emptyCollection(); |
| 348 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
| 349 |
int n = rnd.nextInt(6); |
| 350 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
| 351 |
ArrayList iterated = new ArrayList(); |
| 352 |
ArrayList iteratedForEachRemaining = new ArrayList(); |
| 353 |
ArrayList tryAdvanced = new ArrayList(); |
| 354 |
ArrayList spliterated = new ArrayList(); |
| 355 |
ArrayList forEached = new ArrayList(); |
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ArrayList removeIfed = new ArrayList(); |
| 357 |
for (Object x : c) iterated.add(x); |
| 358 |
c.iterator().forEachRemaining(iteratedForEachRemaining::add); |
| 359 |
for (Spliterator s = c.spliterator(); |
| 360 |
s.tryAdvance(tryAdvanced::add); ) {} |
| 361 |
c.spliterator().forEachRemaining(spliterated::add); |
| 362 |
c.forEach(forEached::add); |
| 363 |
c.removeIf(e -> { removeIfed.add(e); return false; }); |
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boolean ordered = |
| 365 |
c.spliterator().hasCharacteristics(Spliterator.ORDERED); |
| 366 |
if (c instanceof List || c instanceof Deque) |
| 367 |
assertTrue(ordered); |
| 368 |
if (ordered) { |
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assertEquals(iterated, iteratedForEachRemaining); |
| 370 |
assertEquals(iterated, tryAdvanced); |
| 371 |
assertEquals(iterated, spliterated); |
| 372 |
assertEquals(iterated, forEached); |
| 373 |
assertEquals(iterated, removeIfed); |
| 374 |
} else { |
| 375 |
HashSet cset = new HashSet(c); |
| 376 |
assertEquals(cset, new HashSet(iterated)); |
| 377 |
assertEquals(cset, new HashSet(iteratedForEachRemaining)); |
| 378 |
assertEquals(cset, new HashSet(tryAdvanced)); |
| 379 |
assertEquals(cset, new HashSet(spliterated)); |
| 380 |
assertEquals(cset, new HashSet(forEached)); |
| 381 |
assertEquals(cset, new HashSet(removeIfed)); |
| 382 |
} |
| 383 |
if (c instanceof Deque) { |
| 384 |
Deque d = (Deque) c; |
| 385 |
ArrayList descending = new ArrayList(); |
| 386 |
ArrayList descendingForEachRemaining = new ArrayList(); |
| 387 |
for (Iterator it = d.descendingIterator(); it.hasNext(); ) |
| 388 |
descending.add(it.next()); |
| 389 |
d.descendingIterator().forEachRemaining( |
| 390 |
e -> descendingForEachRemaining.add(e)); |
| 391 |
Collections.reverse(descending); |
| 392 |
Collections.reverse(descendingForEachRemaining); |
| 393 |
assertEquals(iterated, descending); |
| 394 |
assertEquals(iterated, descendingForEachRemaining); |
| 395 |
} |
| 396 |
} |
| 397 |
|
| 398 |
/** |
| 399 |
* Calling Iterator#remove() after Iterator#forEachRemaining |
| 400 |
* should (maybe) remove last element |
| 401 |
*/ |
| 402 |
public void testRemoveAfterForEachRemaining() { |
| 403 |
Collection c = impl.emptyCollection(); |
| 404 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
| 405 |
testCollection: { |
| 406 |
int n = 3 + rnd.nextInt(2); |
| 407 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
| 408 |
Iterator it = c.iterator(); |
| 409 |
assertTrue(it.hasNext()); |
| 410 |
assertEquals(impl.makeElement(0), it.next()); |
| 411 |
assertTrue(it.hasNext()); |
| 412 |
assertEquals(impl.makeElement(1), it.next()); |
| 413 |
it.forEachRemaining(e -> assertTrue(c.contains(e))); |
| 414 |
if (testImplementationDetails) { |
| 415 |
if (c instanceof java.util.concurrent.ArrayBlockingQueue) { |
| 416 |
assertIteratorExhausted(it); |
| 417 |
} else { |
| 418 |
try { it.remove(); } |
| 419 |
catch (UnsupportedOperationException ok) { |
| 420 |
break testCollection; |
| 421 |
} |
| 422 |
assertEquals(n - 1, c.size()); |
| 423 |
for (int i = 0; i < n - 1; i++) |
| 424 |
assertTrue(c.contains(impl.makeElement(i))); |
| 425 |
assertFalse(c.contains(impl.makeElement(n - 1))); |
| 426 |
} |
| 427 |
} |
| 428 |
} |
| 429 |
if (c instanceof Deque) { |
| 430 |
Deque d = (Deque) impl.emptyCollection(); |
| 431 |
int n = 3 + rnd.nextInt(2); |
| 432 |
for (int i = 0; i < n; i++) d.add(impl.makeElement(i)); |
| 433 |
Iterator it = d.descendingIterator(); |
| 434 |
assertTrue(it.hasNext()); |
| 435 |
assertEquals(impl.makeElement(n - 1), it.next()); |
| 436 |
assertTrue(it.hasNext()); |
| 437 |
assertEquals(impl.makeElement(n - 2), it.next()); |
| 438 |
it.forEachRemaining(e -> assertTrue(c.contains(e))); |
| 439 |
if (testImplementationDetails) { |
| 440 |
it.remove(); |
| 441 |
assertEquals(n - 1, d.size()); |
| 442 |
for (int i = 1; i < n; i++) |
| 443 |
assertTrue(d.contains(impl.makeElement(i))); |
| 444 |
assertFalse(d.contains(impl.makeElement(0))); |
| 445 |
} |
| 446 |
} |
| 447 |
} |
| 448 |
|
| 449 |
/** |
| 450 |
* stream().forEach returns elements in the collection |
| 451 |
*/ |
| 452 |
public void testStreamForEach() throws Throwable { |
| 453 |
final Collection c = impl.emptyCollection(); |
| 454 |
final AtomicLong count = new AtomicLong(0L); |
| 455 |
final Object x = impl.makeElement(1); |
| 456 |
final Object y = impl.makeElement(2); |
| 457 |
final ArrayList found = new ArrayList(); |
| 458 |
Consumer<Object> spy = o -> found.add(o); |
| 459 |
c.stream().forEach(spy); |
| 460 |
assertTrue(found.isEmpty()); |
| 461 |
|
| 462 |
assertTrue(c.add(x)); |
| 463 |
c.stream().forEach(spy); |
| 464 |
assertEquals(Collections.singletonList(x), found); |
| 465 |
found.clear(); |
| 466 |
|
| 467 |
assertTrue(c.add(y)); |
| 468 |
c.stream().forEach(spy); |
| 469 |
assertEquals(2, found.size()); |
| 470 |
assertTrue(found.contains(x)); |
| 471 |
assertTrue(found.contains(y)); |
| 472 |
found.clear(); |
| 473 |
|
| 474 |
c.clear(); |
| 475 |
c.stream().forEach(spy); |
| 476 |
assertTrue(found.isEmpty()); |
| 477 |
} |
| 478 |
|
| 479 |
public void testStreamForEachConcurrentStressTest() throws Throwable { |
| 480 |
if (!impl.isConcurrent()) return; |
| 481 |
final Collection c = impl.emptyCollection(); |
| 482 |
final long testDurationMillis = timeoutMillis(); |
| 483 |
final AtomicBoolean done = new AtomicBoolean(false); |
| 484 |
final Object elt = impl.makeElement(1); |
| 485 |
final Future<?> f1, f2; |
| 486 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
| 487 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
| 488 |
final CountDownLatch threadsStarted = new CountDownLatch(2); |
| 489 |
Runnable checkElt = () -> { |
| 490 |
threadsStarted.countDown(); |
| 491 |
while (!done.get()) |
| 492 |
c.stream().forEach(x -> assertSame(x, elt)); }; |
| 493 |
Runnable addRemove = () -> { |
| 494 |
threadsStarted.countDown(); |
| 495 |
while (!done.get()) { |
| 496 |
assertTrue(c.add(elt)); |
| 497 |
assertTrue(c.remove(elt)); |
| 498 |
}}; |
| 499 |
f1 = pool.submit(checkElt); |
| 500 |
f2 = pool.submit(addRemove); |
| 501 |
Thread.sleep(testDurationMillis); |
| 502 |
} |
| 503 |
assertNull(f1.get(0L, MILLISECONDS)); |
| 504 |
assertNull(f2.get(0L, MILLISECONDS)); |
| 505 |
} |
| 506 |
|
| 507 |
/** |
| 508 |
* collection.forEach returns elements in the collection |
| 509 |
*/ |
| 510 |
public void testForEach() throws Throwable { |
| 511 |
final Collection c = impl.emptyCollection(); |
| 512 |
final AtomicLong count = new AtomicLong(0L); |
| 513 |
final Object x = impl.makeElement(1); |
| 514 |
final Object y = impl.makeElement(2); |
| 515 |
final ArrayList found = new ArrayList(); |
| 516 |
Consumer<Object> spy = o -> found.add(o); |
| 517 |
c.forEach(spy); |
| 518 |
assertTrue(found.isEmpty()); |
| 519 |
|
| 520 |
assertTrue(c.add(x)); |
| 521 |
c.forEach(spy); |
| 522 |
assertEquals(Collections.singletonList(x), found); |
| 523 |
found.clear(); |
| 524 |
|
| 525 |
assertTrue(c.add(y)); |
| 526 |
c.forEach(spy); |
| 527 |
assertEquals(2, found.size()); |
| 528 |
assertTrue(found.contains(x)); |
| 529 |
assertTrue(found.contains(y)); |
| 530 |
found.clear(); |
| 531 |
|
| 532 |
c.clear(); |
| 533 |
c.forEach(spy); |
| 534 |
assertTrue(found.isEmpty()); |
| 535 |
} |
| 536 |
|
| 537 |
/** |
| 538 |
* Motley crew of threads concurrently randomly hammer the collection. |
| 539 |
*/ |
| 540 |
public void testDetectRaces() throws Throwable { |
| 541 |
if (!impl.isConcurrent()) return; |
| 542 |
final ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
| 543 |
final Collection c = impl.emptyCollection(); |
| 544 |
final long testDurationMillis = timeoutMillis(); |
| 545 |
final AtomicBoolean done = new AtomicBoolean(false); |
| 546 |
final Object one = impl.makeElement(1); |
| 547 |
final Object two = impl.makeElement(2); |
| 548 |
final Object[] emptyArray = |
| 549 |
(Object[]) java.lang.reflect.Array.newInstance(one.getClass(), 0); |
| 550 |
final List<Future<?>> futures; |
| 551 |
final Phaser threadsStarted = new Phaser(1); // register this thread |
| 552 |
final Runnable[] frobbers = { |
| 553 |
() -> c.forEach(x -> assertTrue(x == one || x == two)), |
| 554 |
() -> c.stream().forEach(x -> assertTrue(x == one || x == two)), |
| 555 |
() -> c.spliterator().trySplit(), |
| 556 |
() -> { |
| 557 |
Spliterator s = c.spliterator(); |
| 558 |
s.tryAdvance(x -> assertTrue(x == one || x == two)); |
| 559 |
s.trySplit(); |
| 560 |
}, |
| 561 |
() -> { |
| 562 |
Spliterator s = c.spliterator(); |
| 563 |
do {} while (s.tryAdvance(x -> assertTrue(x == one || x == two))); |
| 564 |
}, |
| 565 |
() -> { |
| 566 |
for (Object x : c) assertTrue(x == one || x == two); |
| 567 |
}, |
| 568 |
() -> { |
| 569 |
for (Object x : c.toArray()) assertTrue(x == one || x == two); |
| 570 |
}, |
| 571 |
() -> { |
| 572 |
for (Object x : c.toArray(emptyArray)) assertTrue(x == one || x == two); |
| 573 |
}, |
| 574 |
() -> { |
| 575 |
assertTrue(c.add(one)); |
| 576 |
assertTrue(c.contains(one)); |
| 577 |
assertTrue(c.remove(one)); |
| 578 |
assertFalse(c.contains(one)); |
| 579 |
}, |
| 580 |
() -> { |
| 581 |
assertTrue(c.add(two)); |
| 582 |
assertTrue(c.contains(two)); |
| 583 |
assertTrue(c.remove(two)); |
| 584 |
assertFalse(c.contains(two)); |
| 585 |
}, |
| 586 |
}; |
| 587 |
final List<Runnable> tasks = |
| 588 |
Arrays.stream(frobbers) |
| 589 |
.filter(task -> rnd.nextBoolean()) // random subset |
| 590 |
.map(task -> (Runnable) () -> { |
| 591 |
threadsStarted.arriveAndAwaitAdvance(); |
| 592 |
while (!done.get()) |
| 593 |
task.run(); |
| 594 |
}) |
| 595 |
.collect(Collectors.toList()); |
| 596 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
| 597 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
| 598 |
threadsStarted.bulkRegister(tasks.size()); |
| 599 |
futures = tasks.stream() |
| 600 |
.map(pool::submit) |
| 601 |
.collect(Collectors.toList()); |
| 602 |
threadsStarted.arriveAndDeregister(); |
| 603 |
Thread.sleep(testDurationMillis); |
| 604 |
} |
| 605 |
for (Future future : futures) |
| 606 |
assertNull(future.get(0L, MILLISECONDS)); |
| 607 |
} |
| 608 |
|
| 609 |
/** |
| 610 |
* Spliterators are either IMMUTABLE or truly late-binding or, if |
| 611 |
* concurrent, use the same "late-binding style" of returning |
| 612 |
* elements added between creation and first use. |
| 613 |
*/ |
| 614 |
public void testLateBindingStyle() { |
| 615 |
if (!testImplementationDetails) return; |
| 616 |
// Immutable (snapshot) spliterators are exempt |
| 617 |
if (impl.emptyCollection().spliterator() |
| 618 |
.hasCharacteristics(Spliterator.IMMUTABLE)) |
| 619 |
return; |
| 620 |
final Object one = impl.makeElement(1); |
| 621 |
{ |
| 622 |
final Collection c = impl.emptyCollection(); |
| 623 |
final Spliterator split = c.spliterator(); |
| 624 |
c.add(one); |
| 625 |
assertTrue(split.tryAdvance(e -> { assertSame(e, one); })); |
| 626 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
| 627 |
assertTrue(c.contains(one)); |
| 628 |
} |
| 629 |
{ |
| 630 |
final AtomicLong count = new AtomicLong(0); |
| 631 |
final Collection c = impl.emptyCollection(); |
| 632 |
final Spliterator split = c.spliterator(); |
| 633 |
c.add(one); |
| 634 |
split.forEachRemaining( |
| 635 |
e -> { assertSame(e, one); count.getAndIncrement(); }); |
| 636 |
assertEquals(1L, count.get()); |
| 637 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
| 638 |
assertTrue(c.contains(one)); |
| 639 |
} |
| 640 |
} |
| 641 |
|
| 642 |
// public void testCollection8DebugFail() { |
| 643 |
// fail(impl.klazz().getSimpleName()); |
| 644 |
// } |
| 645 |
} |
