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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.ConcurrentModificationException; |
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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.Set; |
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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.ConcurrentLinkedQueue; |
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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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@Override public boolean equals(Object x) { throw new AssertionError(); } |
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@Override public int hashCode() { throw new AssertionError(); } |
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@Override public String toString() { 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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if (c instanceof List<?>) { |
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List x = (List) c; |
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assertEquals(1, x.hashCode()); |
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assertEquals(x, Collections.emptyList()); |
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assertEquals(Collections.emptyList(), x); |
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assertEquals(-1, x.indexOf(impl.makeElement(86))); |
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assertEquals(-1, x.lastIndexOf(impl.makeElement(99))); |
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} |
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else if (c instanceof Set<?>) { |
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assertEquals(0, c.hashCode()); |
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assertEquals(c, Collections.emptySet()); |
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assertEquals(Collections.emptySet(), c); |
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} |
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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(randomExpiredTimeout(), randomTimeUnit())); |
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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(randomExpiredTimeout(), randomTimeUnit())); |
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assertNull(q.pollLast(randomExpiredTimeout(), randomTimeUnit())); |
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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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if (c instanceof List) { |
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List x = (List) c; |
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assertThrows( |
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NoSuchElementException.class, |
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() -> x.iterator().next(), |
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() -> x.listIterator().next(), |
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() -> x.listIterator(0).next(), |
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() -> x.listIterator().previous(), |
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() -> x.listIterator(0).previous()); |
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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())); |
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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; |
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case 2: c.forEach(survivors::add); break; |
335 |
case 3: for (Object e : c) survivors.add(e); break; |
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} |
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assertTrue(orig.containsAll(accepts)); |
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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)); |
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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)); |
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} 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); |
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} |
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} catch (Throwable ex) { |
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System.err.println(impl.klazz()); |
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// 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); } |
359 |
catch (Throwable t) { t.printStackTrace(); } |
360 |
System.err.printf("n=%d%n", n); |
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System.err.printf("orig=%s%n", orig); |
362 |
System.err.printf("accepts=%s%n", accepts); |
363 |
System.err.printf("rejects=%s%n", rejects); |
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System.err.printf("survivors=%s%n", survivors); |
365 |
System.err.printf("threwAt=%s%n", threwAt.get()); |
366 |
throw ex; |
367 |
} |
368 |
} |
369 |
|
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/** |
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* All elements removed in the middle of CONCURRENT traversal. |
372 |
*/ |
373 |
public void testElementRemovalDuringTraversal() { |
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Collection c = impl.emptyCollection(); |
375 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
376 |
int n = rnd.nextInt(6); |
377 |
ArrayList copy = new ArrayList(); |
378 |
for (int i = 0; i < n; i++) { |
379 |
Object x = impl.makeElement(i); |
380 |
copy.add(x); |
381 |
c.add(x); |
382 |
} |
383 |
ArrayList iterated = new ArrayList(); |
384 |
ArrayList spliterated = new ArrayList(); |
385 |
Spliterator s = c.spliterator(); |
386 |
Iterator it = c.iterator(); |
387 |
for (int i = rnd.nextInt(n + 1); --i >= 0; ) { |
388 |
assertTrue(s.tryAdvance(spliterated::add)); |
389 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
390 |
iterated.add(it.next()); |
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} |
392 |
Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
393 |
if (s.hasCharacteristics(Spliterator.CONCURRENT)) { |
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c.clear(); // TODO: many more removal methods |
395 |
if (testImplementationDetails |
396 |
&& !(c instanceof java.util.concurrent.ArrayBlockingQueue)) { |
397 |
if (rnd.nextBoolean()) |
398 |
assertFalse(s.tryAdvance(alwaysThrows)); |
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else |
400 |
s.forEachRemaining(alwaysThrows); |
401 |
} |
402 |
if (it.hasNext()) iterated.add(it.next()); |
403 |
if (rnd.nextBoolean()) assertIteratorExhausted(it); |
404 |
} |
405 |
assertTrue(copy.containsAll(iterated)); |
406 |
assertTrue(copy.containsAll(spliterated)); |
407 |
} |
408 |
|
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/** |
410 |
* Some elements randomly disappear in the middle of traversal. |
411 |
*/ |
412 |
public void testRandomElementRemovalDuringTraversal() { |
413 |
Collection c = impl.emptyCollection(); |
414 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
415 |
int n = rnd.nextInt(6); |
416 |
ArrayList copy = new ArrayList(); |
417 |
for (int i = 0; i < n; i++) { |
418 |
Object x = impl.makeElement(i); |
419 |
copy.add(x); |
420 |
c.add(x); |
421 |
} |
422 |
ArrayList iterated = new ArrayList(); |
423 |
ArrayList spliterated = new ArrayList(); |
424 |
ArrayList removed = new ArrayList(); |
425 |
Spliterator s = c.spliterator(); |
426 |
Iterator it = c.iterator(); |
427 |
if (! (s.hasCharacteristics(Spliterator.CONCURRENT) || |
428 |
s.hasCharacteristics(Spliterator.IMMUTABLE))) |
429 |
return; |
430 |
for (int i = rnd.nextInt(n + 1); --i >= 0; ) { |
431 |
assertTrue(s.tryAdvance(e -> {})); |
432 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
433 |
it.next(); |
434 |
} |
435 |
Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
436 |
// TODO: many more removal methods |
437 |
if (rnd.nextBoolean()) { |
438 |
for (Iterator z = c.iterator(); z.hasNext(); ) { |
439 |
Object e = z.next(); |
440 |
if (rnd.nextBoolean()) { |
441 |
try { |
442 |
z.remove(); |
443 |
} catch (UnsupportedOperationException ok) { return; } |
444 |
removed.add(e); |
445 |
} |
446 |
} |
447 |
} else { |
448 |
Predicate randomlyRemove = e -> { |
449 |
if (rnd.nextBoolean()) { removed.add(e); return true; } |
450 |
else return false; |
451 |
}; |
452 |
c.removeIf(randomlyRemove); |
453 |
} |
454 |
s.forEachRemaining(spliterated::add); |
455 |
while (it.hasNext()) |
456 |
iterated.add(it.next()); |
457 |
assertTrue(copy.containsAll(iterated)); |
458 |
assertTrue(copy.containsAll(spliterated)); |
459 |
assertTrue(copy.containsAll(removed)); |
460 |
if (s.hasCharacteristics(Spliterator.CONCURRENT)) { |
461 |
ArrayList iteratedAndRemoved = new ArrayList(iterated); |
462 |
ArrayList spliteratedAndRemoved = new ArrayList(spliterated); |
463 |
iteratedAndRemoved.retainAll(removed); |
464 |
spliteratedAndRemoved.retainAll(removed); |
465 |
assertTrue(iteratedAndRemoved.size() <= 1); |
466 |
assertTrue(spliteratedAndRemoved.size() <= 1); |
467 |
if (testImplementationDetails |
468 |
&& !(c instanceof java.util.concurrent.ArrayBlockingQueue)) |
469 |
assertTrue(spliteratedAndRemoved.isEmpty()); |
470 |
} |
471 |
} |
472 |
|
473 |
/** |
474 |
* Various ways of traversing a collection yield same elements |
475 |
*/ |
476 |
public void testTraversalEquivalence() { |
477 |
Collection c = impl.emptyCollection(); |
478 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
479 |
int n = rnd.nextInt(6); |
480 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
481 |
ArrayList iterated = new ArrayList(); |
482 |
ArrayList iteratedForEachRemaining = new ArrayList(); |
483 |
ArrayList tryAdvanced = new ArrayList(); |
484 |
ArrayList spliterated = new ArrayList(); |
485 |
ArrayList splitonced = new ArrayList(); |
486 |
ArrayList forEached = new ArrayList(); |
487 |
ArrayList streamForEached = new ArrayList(); |
488 |
ConcurrentLinkedQueue parallelStreamForEached = new ConcurrentLinkedQueue(); |
489 |
ArrayList removeIfed = new ArrayList(); |
490 |
for (Object x : c) iterated.add(x); |
491 |
c.iterator().forEachRemaining(iteratedForEachRemaining::add); |
492 |
for (Spliterator s = c.spliterator(); |
493 |
s.tryAdvance(tryAdvanced::add); ) {} |
494 |
c.spliterator().forEachRemaining(spliterated::add); |
495 |
{ // trySplit returns "strict prefix" |
496 |
Spliterator s1 = c.spliterator(), s2 = s1.trySplit(); |
497 |
if (s2 != null) s2.forEachRemaining(splitonced::add); |
498 |
s1.forEachRemaining(splitonced::add); |
499 |
} |
500 |
c.forEach(forEached::add); |
501 |
c.stream().forEach(streamForEached::add); |
502 |
c.parallelStream().forEach(parallelStreamForEached::add); |
503 |
c.removeIf(e -> { removeIfed.add(e); return false; }); |
504 |
boolean ordered = |
505 |
c.spliterator().hasCharacteristics(Spliterator.ORDERED); |
506 |
if (c instanceof List || c instanceof Deque) |
507 |
assertTrue(ordered); |
508 |
HashSet cset = new HashSet(c); |
509 |
assertEquals(cset, new HashSet(parallelStreamForEached)); |
510 |
if (ordered) { |
511 |
assertEquals(iterated, iteratedForEachRemaining); |
512 |
assertEquals(iterated, tryAdvanced); |
513 |
assertEquals(iterated, spliterated); |
514 |
assertEquals(iterated, splitonced); |
515 |
assertEquals(iterated, forEached); |
516 |
assertEquals(iterated, streamForEached); |
517 |
assertEquals(iterated, removeIfed); |
518 |
} else { |
519 |
assertEquals(cset, new HashSet(iterated)); |
520 |
assertEquals(cset, new HashSet(iteratedForEachRemaining)); |
521 |
assertEquals(cset, new HashSet(tryAdvanced)); |
522 |
assertEquals(cset, new HashSet(spliterated)); |
523 |
assertEquals(cset, new HashSet(splitonced)); |
524 |
assertEquals(cset, new HashSet(forEached)); |
525 |
assertEquals(cset, new HashSet(streamForEached)); |
526 |
assertEquals(cset, new HashSet(removeIfed)); |
527 |
} |
528 |
if (c instanceof Deque) { |
529 |
Deque d = (Deque) c; |
530 |
ArrayList descending = new ArrayList(); |
531 |
ArrayList descendingForEachRemaining = new ArrayList(); |
532 |
for (Iterator it = d.descendingIterator(); it.hasNext(); ) |
533 |
descending.add(it.next()); |
534 |
d.descendingIterator().forEachRemaining( |
535 |
e -> descendingForEachRemaining.add(e)); |
536 |
Collections.reverse(descending); |
537 |
Collections.reverse(descendingForEachRemaining); |
538 |
assertEquals(iterated, descending); |
539 |
assertEquals(iterated, descendingForEachRemaining); |
540 |
} |
541 |
} |
542 |
|
543 |
/** |
544 |
* Iterator.forEachRemaining has same behavior as Iterator's |
545 |
* default implementation. |
546 |
*/ |
547 |
public void testForEachRemainingConsistentWithDefaultImplementation() { |
548 |
Collection c = impl.emptyCollection(); |
549 |
if (!testImplementationDetails |
550 |
|| c.getClass() == java.util.LinkedList.class) |
551 |
return; |
552 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
553 |
int n = 1 + rnd.nextInt(3); |
554 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
555 |
ArrayList iterated = new ArrayList(); |
556 |
ArrayList iteratedForEachRemaining = new ArrayList(); |
557 |
Iterator it1 = c.iterator(); |
558 |
Iterator it2 = c.iterator(); |
559 |
assertTrue(it1.hasNext()); |
560 |
assertTrue(it2.hasNext()); |
561 |
c.clear(); |
562 |
Object r1, r2; |
563 |
try { |
564 |
while (it1.hasNext()) iterated.add(it1.next()); |
565 |
r1 = iterated; |
566 |
} catch (ConcurrentModificationException ex) { |
567 |
r1 = ConcurrentModificationException.class; |
568 |
assertFalse(impl.isConcurrent()); |
569 |
} |
570 |
try { |
571 |
it2.forEachRemaining(iteratedForEachRemaining::add); |
572 |
r2 = iteratedForEachRemaining; |
573 |
} catch (ConcurrentModificationException ex) { |
574 |
r2 = ConcurrentModificationException.class; |
575 |
assertFalse(impl.isConcurrent()); |
576 |
} |
577 |
assertEquals(r1, r2); |
578 |
} |
579 |
|
580 |
/** |
581 |
* Calling Iterator#remove() after Iterator#forEachRemaining |
582 |
* should (maybe) remove last element |
583 |
*/ |
584 |
public void testRemoveAfterForEachRemaining() { |
585 |
Collection c = impl.emptyCollection(); |
586 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
587 |
testCollection: { |
588 |
int n = 3 + rnd.nextInt(2); |
589 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
590 |
Iterator it = c.iterator(); |
591 |
assertTrue(it.hasNext()); |
592 |
assertEquals(impl.makeElement(0), it.next()); |
593 |
assertTrue(it.hasNext()); |
594 |
assertEquals(impl.makeElement(1), it.next()); |
595 |
it.forEachRemaining(e -> assertTrue(c.contains(e))); |
596 |
if (testImplementationDetails) { |
597 |
if (c instanceof java.util.concurrent.ArrayBlockingQueue) { |
598 |
assertIteratorExhausted(it); |
599 |
} else { |
600 |
try { it.remove(); } |
601 |
catch (UnsupportedOperationException ok) { |
602 |
break testCollection; |
603 |
} |
604 |
assertEquals(n - 1, c.size()); |
605 |
for (int i = 0; i < n - 1; i++) |
606 |
assertTrue(c.contains(impl.makeElement(i))); |
607 |
assertFalse(c.contains(impl.makeElement(n - 1))); |
608 |
} |
609 |
} |
610 |
} |
611 |
if (c instanceof Deque) { |
612 |
Deque d = (Deque) impl.emptyCollection(); |
613 |
int n = 3 + rnd.nextInt(2); |
614 |
for (int i = 0; i < n; i++) d.add(impl.makeElement(i)); |
615 |
Iterator it = d.descendingIterator(); |
616 |
assertTrue(it.hasNext()); |
617 |
assertEquals(impl.makeElement(n - 1), it.next()); |
618 |
assertTrue(it.hasNext()); |
619 |
assertEquals(impl.makeElement(n - 2), it.next()); |
620 |
it.forEachRemaining(e -> assertTrue(c.contains(e))); |
621 |
if (testImplementationDetails) { |
622 |
it.remove(); |
623 |
assertEquals(n - 1, d.size()); |
624 |
for (int i = 1; i < n; i++) |
625 |
assertTrue(d.contains(impl.makeElement(i))); |
626 |
assertFalse(d.contains(impl.makeElement(0))); |
627 |
} |
628 |
} |
629 |
} |
630 |
|
631 |
/** |
632 |
* stream().forEach returns elements in the collection |
633 |
*/ |
634 |
public void testStreamForEach() throws Throwable { |
635 |
final Collection c = impl.emptyCollection(); |
636 |
final AtomicLong count = new AtomicLong(0L); |
637 |
final Object x = impl.makeElement(1); |
638 |
final Object y = impl.makeElement(2); |
639 |
final ArrayList found = new ArrayList(); |
640 |
Consumer<Object> spy = o -> found.add(o); |
641 |
c.stream().forEach(spy); |
642 |
assertTrue(found.isEmpty()); |
643 |
|
644 |
assertTrue(c.add(x)); |
645 |
c.stream().forEach(spy); |
646 |
assertEquals(Collections.singletonList(x), found); |
647 |
found.clear(); |
648 |
|
649 |
assertTrue(c.add(y)); |
650 |
c.stream().forEach(spy); |
651 |
assertEquals(2, found.size()); |
652 |
assertTrue(found.contains(x)); |
653 |
assertTrue(found.contains(y)); |
654 |
found.clear(); |
655 |
|
656 |
c.clear(); |
657 |
c.stream().forEach(spy); |
658 |
assertTrue(found.isEmpty()); |
659 |
} |
660 |
|
661 |
public void testStreamForEachConcurrentStressTest() throws Throwable { |
662 |
if (!impl.isConcurrent()) return; |
663 |
final Collection c = impl.emptyCollection(); |
664 |
final long testDurationMillis = timeoutMillis(); |
665 |
final AtomicBoolean done = new AtomicBoolean(false); |
666 |
final Object elt = impl.makeElement(1); |
667 |
final Future<?> f1, f2; |
668 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
669 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
670 |
final CountDownLatch threadsStarted = new CountDownLatch(2); |
671 |
Runnable checkElt = () -> { |
672 |
threadsStarted.countDown(); |
673 |
while (!done.get()) |
674 |
c.stream().forEach(x -> assertSame(x, elt)); }; |
675 |
Runnable addRemove = () -> { |
676 |
threadsStarted.countDown(); |
677 |
while (!done.get()) { |
678 |
assertTrue(c.add(elt)); |
679 |
assertTrue(c.remove(elt)); |
680 |
}}; |
681 |
f1 = pool.submit(checkElt); |
682 |
f2 = pool.submit(addRemove); |
683 |
Thread.sleep(testDurationMillis); |
684 |
} |
685 |
assertNull(f1.get(0L, MILLISECONDS)); |
686 |
assertNull(f2.get(0L, MILLISECONDS)); |
687 |
} |
688 |
|
689 |
/** |
690 |
* collection.forEach returns elements in the collection |
691 |
*/ |
692 |
public void testForEach() throws Throwable { |
693 |
final Collection c = impl.emptyCollection(); |
694 |
final AtomicLong count = new AtomicLong(0L); |
695 |
final Object x = impl.makeElement(1); |
696 |
final Object y = impl.makeElement(2); |
697 |
final ArrayList found = new ArrayList(); |
698 |
Consumer<Object> spy = o -> found.add(o); |
699 |
c.forEach(spy); |
700 |
assertTrue(found.isEmpty()); |
701 |
|
702 |
assertTrue(c.add(x)); |
703 |
c.forEach(spy); |
704 |
assertEquals(Collections.singletonList(x), found); |
705 |
found.clear(); |
706 |
|
707 |
assertTrue(c.add(y)); |
708 |
c.forEach(spy); |
709 |
assertEquals(2, found.size()); |
710 |
assertTrue(found.contains(x)); |
711 |
assertTrue(found.contains(y)); |
712 |
found.clear(); |
713 |
|
714 |
c.clear(); |
715 |
c.forEach(spy); |
716 |
assertTrue(found.isEmpty()); |
717 |
} |
718 |
|
719 |
/** TODO: promote to a common utility */ |
720 |
static <T> T chooseOne(T ... ts) { |
721 |
return ts[ThreadLocalRandom.current().nextInt(ts.length)]; |
722 |
} |
723 |
|
724 |
/** TODO: more random adders and removers */ |
725 |
static <E> Runnable adderRemover(Collection<E> c, E e) { |
726 |
return chooseOne( |
727 |
() -> { |
728 |
assertTrue(c.add(e)); |
729 |
assertTrue(c.contains(e)); |
730 |
assertTrue(c.remove(e)); |
731 |
assertFalse(c.contains(e)); |
732 |
}, |
733 |
() -> { |
734 |
assertTrue(c.add(e)); |
735 |
assertTrue(c.contains(e)); |
736 |
assertTrue(c.removeIf(x -> x == e)); |
737 |
assertFalse(c.contains(e)); |
738 |
}, |
739 |
() -> { |
740 |
assertTrue(c.add(e)); |
741 |
assertTrue(c.contains(e)); |
742 |
for (Iterator it = c.iterator();; ) |
743 |
if (it.next() == e) { |
744 |
try { it.remove(); } |
745 |
catch (UnsupportedOperationException ok) { |
746 |
c.remove(e); |
747 |
} |
748 |
break; |
749 |
} |
750 |
assertFalse(c.contains(e)); |
751 |
}); |
752 |
} |
753 |
|
754 |
/** |
755 |
* Concurrent Spliterators, once exhausted, stay exhausted. |
756 |
*/ |
757 |
public void testStickySpliteratorExhaustion() throws Throwable { |
758 |
if (!impl.isConcurrent()) return; |
759 |
if (!testImplementationDetails) return; |
760 |
final ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
761 |
final Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
762 |
final Collection c = impl.emptyCollection(); |
763 |
final Spliterator s = c.spliterator(); |
764 |
if (rnd.nextBoolean()) { |
765 |
assertFalse(s.tryAdvance(alwaysThrows)); |
766 |
} else { |
767 |
s.forEachRemaining(alwaysThrows); |
768 |
} |
769 |
final Object one = impl.makeElement(1); |
770 |
// Spliterator should not notice added element |
771 |
c.add(one); |
772 |
if (rnd.nextBoolean()) { |
773 |
assertFalse(s.tryAdvance(alwaysThrows)); |
774 |
} else { |
775 |
s.forEachRemaining(alwaysThrows); |
776 |
} |
777 |
} |
778 |
|
779 |
/** |
780 |
* Motley crew of threads concurrently randomly hammer the collection. |
781 |
*/ |
782 |
public void testDetectRaces() throws Throwable { |
783 |
if (!impl.isConcurrent()) return; |
784 |
final ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
785 |
final Collection c = impl.emptyCollection(); |
786 |
final long testDurationMillis |
787 |
= expensiveTests ? LONG_DELAY_MS : timeoutMillis(); |
788 |
final AtomicBoolean done = new AtomicBoolean(false); |
789 |
final Object one = impl.makeElement(1); |
790 |
final Object two = impl.makeElement(2); |
791 |
final Consumer checkSanity = x -> assertTrue(x == one || x == two); |
792 |
final Consumer<Object[]> checkArraySanity = array -> { |
793 |
// assertTrue(array.length <= 2); // duplicates are permitted |
794 |
for (Object x : array) assertTrue(x == one || x == two); |
795 |
}; |
796 |
final Object[] emptyArray = |
797 |
(Object[]) java.lang.reflect.Array.newInstance(one.getClass(), 0); |
798 |
final List<Future<?>> futures; |
799 |
final Phaser threadsStarted = new Phaser(1); // register this thread |
800 |
final Runnable[] frobbers = { |
801 |
() -> c.forEach(checkSanity), |
802 |
() -> c.stream().forEach(checkSanity), |
803 |
() -> c.parallelStream().forEach(checkSanity), |
804 |
() -> c.spliterator().trySplit(), |
805 |
() -> { |
806 |
Spliterator s = c.spliterator(); |
807 |
s.tryAdvance(checkSanity); |
808 |
s.trySplit(); |
809 |
}, |
810 |
() -> { |
811 |
Spliterator s = c.spliterator(); |
812 |
do {} while (s.tryAdvance(checkSanity)); |
813 |
}, |
814 |
() -> { for (Object x : c) checkSanity.accept(x); }, |
815 |
() -> checkArraySanity.accept(c.toArray()), |
816 |
() -> checkArraySanity.accept(c.toArray(emptyArray)), |
817 |
() -> { |
818 |
Object[] a = new Object[5]; |
819 |
Object three = impl.makeElement(3); |
820 |
Arrays.fill(a, 0, a.length, three); |
821 |
Object[] x = c.toArray(a); |
822 |
if (x == a) |
823 |
for (int i = 0; i < a.length && a[i] != null; i++) |
824 |
checkSanity.accept(a[i]); |
825 |
// A careful reading of the spec does not support: |
826 |
// for (i++; i < a.length; i++) assertSame(three, a[i]); |
827 |
else |
828 |
checkArraySanity.accept(x); |
829 |
}, |
830 |
adderRemover(c, one), |
831 |
adderRemover(c, two), |
832 |
}; |
833 |
final List<Runnable> tasks = |
834 |
Arrays.stream(frobbers) |
835 |
.filter(task -> rnd.nextBoolean()) // random subset |
836 |
.map(task -> (Runnable) () -> { |
837 |
threadsStarted.arriveAndAwaitAdvance(); |
838 |
while (!done.get()) |
839 |
task.run(); |
840 |
}) |
841 |
.collect(Collectors.toList()); |
842 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
843 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
844 |
threadsStarted.bulkRegister(tasks.size()); |
845 |
futures = tasks.stream() |
846 |
.map(pool::submit) |
847 |
.collect(Collectors.toList()); |
848 |
threadsStarted.arriveAndDeregister(); |
849 |
Thread.sleep(testDurationMillis); |
850 |
} |
851 |
for (Future future : futures) |
852 |
assertNull(future.get(0L, MILLISECONDS)); |
853 |
} |
854 |
|
855 |
/** |
856 |
* Spliterators are either IMMUTABLE or truly late-binding or, if |
857 |
* concurrent, use the same "late-binding style" of returning |
858 |
* elements added between creation and first use. |
859 |
*/ |
860 |
public void testLateBindingStyle() { |
861 |
if (!testImplementationDetails) return; |
862 |
if (impl.klazz() == ArrayList.class) return; // for jdk8 |
863 |
// Immutable (snapshot) spliterators are exempt |
864 |
if (impl.emptyCollection().spliterator() |
865 |
.hasCharacteristics(Spliterator.IMMUTABLE)) |
866 |
return; |
867 |
final Object one = impl.makeElement(1); |
868 |
{ |
869 |
final Collection c = impl.emptyCollection(); |
870 |
final Spliterator split = c.spliterator(); |
871 |
c.add(one); |
872 |
assertTrue(split.tryAdvance(e -> { assertSame(e, one); })); |
873 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
874 |
assertTrue(c.contains(one)); |
875 |
} |
876 |
{ |
877 |
final AtomicLong count = new AtomicLong(0); |
878 |
final Collection c = impl.emptyCollection(); |
879 |
final Spliterator split = c.spliterator(); |
880 |
c.add(one); |
881 |
split.forEachRemaining( |
882 |
e -> { assertSame(e, one); count.getAndIncrement(); }); |
883 |
assertEquals(1L, count.get()); |
884 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
885 |
assertTrue(c.contains(one)); |
886 |
} |
887 |
} |
888 |
|
889 |
/** |
890 |
* Spliterator.getComparator throws IllegalStateException iff the |
891 |
* spliterator does not report SORTED. |
892 |
*/ |
893 |
public void testGetComparator_IllegalStateException() { |
894 |
Collection c = impl.emptyCollection(); |
895 |
Spliterator s = c.spliterator(); |
896 |
boolean reportsSorted = s.hasCharacteristics(Spliterator.SORTED); |
897 |
try { |
898 |
s.getComparator(); |
899 |
assertTrue(reportsSorted); |
900 |
} catch (IllegalStateException ex) { |
901 |
assertFalse(reportsSorted); |
902 |
} |
903 |
} |
904 |
|
905 |
// public void testCollection8DebugFail() { |
906 |
// fail(impl.klazz().getSimpleName()); |
907 |
// } |
908 |
} |