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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.ArrayDeque; |
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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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assertThrows( |
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IndexOutOfBoundsException.class, |
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() -> x.get(0), |
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() -> x.set(0, impl.makeElement(42))); |
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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((Object[])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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() -> q.offer(null, 1L, HOURS), |
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() -> q.put(null)); |
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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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() -> q.offerFirst(null, 1L, HOURS), |
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() -> q.offerLast(null, 1L, HOURS), |
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() -> q.putFirst(null), |
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() -> q.putLast(null)); |
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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; |
315 |
case 2: c.forEach(survivors::add); break; |
316 |
case 3: for (Object e : c) survivors.add(e); break; |
317 |
} |
318 |
assertTrue(orig.containsAll(accepts)); |
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assertTrue(orig.containsAll(rejects)); |
320 |
assertTrue(orig.containsAll(survivors)); |
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assertTrue(orig.containsAll(c)); |
322 |
assertTrue(c.containsAll(rejects)); |
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assertTrue(c.containsAll(survivors)); |
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assertTrue(survivors.containsAll(rejects)); |
325 |
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)); |
328 |
} 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()); |
332 |
int k = 0; |
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for (Object x : accepts) if (c.contains(x)) k++; |
334 |
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()); |
338 |
// 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); } |
340 |
catch (Throwable t) { t.printStackTrace(); } |
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System.err.printf("n=%d%n", n); |
342 |
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); |
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System.err.printf("survivors=%s%n", survivors); |
346 |
System.err.printf("threwAt=%s%n", threwAt.get()); |
347 |
throw ex; |
348 |
} |
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} |
350 |
|
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/** |
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* All elements removed in the middle of CONCURRENT traversal. |
353 |
*/ |
354 |
public void testElementRemovalDuringTraversal() { |
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Collection c = impl.emptyCollection(); |
356 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
357 |
int n = rnd.nextInt(6); |
358 |
ArrayList copy = new ArrayList(); |
359 |
for (int i = 0; i < n; i++) { |
360 |
Object x = impl.makeElement(i); |
361 |
copy.add(x); |
362 |
c.add(x); |
363 |
} |
364 |
ArrayList iterated = new ArrayList(); |
365 |
ArrayList spliterated = new ArrayList(); |
366 |
Spliterator s = c.spliterator(); |
367 |
Iterator it = c.iterator(); |
368 |
for (int i = rnd.nextInt(n + 1); --i >= 0; ) { |
369 |
assertTrue(s.tryAdvance(spliterated::add)); |
370 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
371 |
iterated.add(it.next()); |
372 |
} |
373 |
Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
374 |
if (s.hasCharacteristics(Spliterator.CONCURRENT)) { |
375 |
c.clear(); // TODO: many more removal methods |
376 |
if (testImplementationDetails |
377 |
&& !(c instanceof java.util.concurrent.ArrayBlockingQueue)) { |
378 |
if (rnd.nextBoolean()) |
379 |
assertFalse(s.tryAdvance(alwaysThrows)); |
380 |
else |
381 |
s.forEachRemaining(alwaysThrows); |
382 |
} |
383 |
if (it.hasNext()) iterated.add(it.next()); |
384 |
if (rnd.nextBoolean()) assertIteratorExhausted(it); |
385 |
} |
386 |
assertTrue(copy.containsAll(iterated)); |
387 |
assertTrue(copy.containsAll(spliterated)); |
388 |
} |
389 |
|
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/** |
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* Some elements randomly disappear in the middle of traversal. |
392 |
*/ |
393 |
public void testRandomElementRemovalDuringTraversal() { |
394 |
Collection c = impl.emptyCollection(); |
395 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
396 |
int n = rnd.nextInt(6); |
397 |
ArrayList copy = new ArrayList(); |
398 |
for (int i = 0; i < n; i++) { |
399 |
Object x = impl.makeElement(i); |
400 |
copy.add(x); |
401 |
c.add(x); |
402 |
} |
403 |
ArrayList iterated = new ArrayList(); |
404 |
ArrayList spliterated = new ArrayList(); |
405 |
ArrayList removed = new ArrayList(); |
406 |
Spliterator s = c.spliterator(); |
407 |
Iterator it = c.iterator(); |
408 |
if (! (s.hasCharacteristics(Spliterator.CONCURRENT) || |
409 |
s.hasCharacteristics(Spliterator.IMMUTABLE))) |
410 |
return; |
411 |
for (int i = rnd.nextInt(n + 1); --i >= 0; ) { |
412 |
assertTrue(s.tryAdvance(e -> {})); |
413 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
414 |
it.next(); |
415 |
} |
416 |
Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
417 |
// TODO: many more removal methods |
418 |
if (rnd.nextBoolean()) { |
419 |
for (Iterator z = c.iterator(); z.hasNext(); ) { |
420 |
Object e = z.next(); |
421 |
if (rnd.nextBoolean()) { |
422 |
try { |
423 |
z.remove(); |
424 |
} catch (UnsupportedOperationException ok) { return; } |
425 |
removed.add(e); |
426 |
} |
427 |
} |
428 |
} else { |
429 |
Predicate randomlyRemove = e -> { |
430 |
if (rnd.nextBoolean()) { removed.add(e); return true; } |
431 |
else return false; |
432 |
}; |
433 |
c.removeIf(randomlyRemove); |
434 |
} |
435 |
s.forEachRemaining(spliterated::add); |
436 |
while (it.hasNext()) |
437 |
iterated.add(it.next()); |
438 |
assertTrue(copy.containsAll(iterated)); |
439 |
assertTrue(copy.containsAll(spliterated)); |
440 |
assertTrue(copy.containsAll(removed)); |
441 |
if (s.hasCharacteristics(Spliterator.CONCURRENT)) { |
442 |
ArrayList iteratedAndRemoved = new ArrayList(iterated); |
443 |
ArrayList spliteratedAndRemoved = new ArrayList(spliterated); |
444 |
iteratedAndRemoved.retainAll(removed); |
445 |
spliteratedAndRemoved.retainAll(removed); |
446 |
assertTrue(iteratedAndRemoved.size() <= 1); |
447 |
assertTrue(spliteratedAndRemoved.size() <= 1); |
448 |
if (testImplementationDetails |
449 |
&& !(c instanceof java.util.concurrent.ArrayBlockingQueue)) |
450 |
assertTrue(spliteratedAndRemoved.isEmpty()); |
451 |
} |
452 |
} |
453 |
|
454 |
/** |
455 |
* Various ways of traversing a collection yield same elements |
456 |
*/ |
457 |
public void testTraversalEquivalence() { |
458 |
Collection c = impl.emptyCollection(); |
459 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
460 |
int n = rnd.nextInt(6); |
461 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
462 |
ArrayList iterated = new ArrayList(); |
463 |
ArrayList iteratedForEachRemaining = new ArrayList(); |
464 |
ArrayList tryAdvanced = new ArrayList(); |
465 |
ArrayList spliterated = new ArrayList(); |
466 |
ArrayList splitonced = new ArrayList(); |
467 |
ArrayList forEached = new ArrayList(); |
468 |
ArrayList streamForEached = new ArrayList(); |
469 |
ConcurrentLinkedQueue parallelStreamForEached = new ConcurrentLinkedQueue(); |
470 |
ArrayList removeIfed = new ArrayList(); |
471 |
for (Object x : c) iterated.add(x); |
472 |
c.iterator().forEachRemaining(iteratedForEachRemaining::add); |
473 |
for (Spliterator s = c.spliterator(); |
474 |
s.tryAdvance(tryAdvanced::add); ) {} |
475 |
c.spliterator().forEachRemaining(spliterated::add); |
476 |
{ // trySplit returns "strict prefix" |
477 |
Spliterator s1 = c.spliterator(), s2 = s1.trySplit(); |
478 |
if (s2 != null) s2.forEachRemaining(splitonced::add); |
479 |
s1.forEachRemaining(splitonced::add); |
480 |
} |
481 |
c.forEach(forEached::add); |
482 |
c.stream().forEach(streamForEached::add); |
483 |
c.parallelStream().forEach(parallelStreamForEached::add); |
484 |
c.removeIf(e -> { removeIfed.add(e); return false; }); |
485 |
boolean ordered = |
486 |
c.spliterator().hasCharacteristics(Spliterator.ORDERED); |
487 |
if (c instanceof List || c instanceof Deque) |
488 |
assertTrue(ordered); |
489 |
HashSet cset = new HashSet(c); |
490 |
assertEquals(cset, new HashSet(parallelStreamForEached)); |
491 |
if (ordered) { |
492 |
assertEquals(iterated, iteratedForEachRemaining); |
493 |
assertEquals(iterated, tryAdvanced); |
494 |
assertEquals(iterated, spliterated); |
495 |
assertEquals(iterated, splitonced); |
496 |
assertEquals(iterated, forEached); |
497 |
assertEquals(iterated, streamForEached); |
498 |
assertEquals(iterated, removeIfed); |
499 |
} else { |
500 |
assertEquals(cset, new HashSet(iterated)); |
501 |
assertEquals(cset, new HashSet(iteratedForEachRemaining)); |
502 |
assertEquals(cset, new HashSet(tryAdvanced)); |
503 |
assertEquals(cset, new HashSet(spliterated)); |
504 |
assertEquals(cset, new HashSet(splitonced)); |
505 |
assertEquals(cset, new HashSet(forEached)); |
506 |
assertEquals(cset, new HashSet(streamForEached)); |
507 |
assertEquals(cset, new HashSet(removeIfed)); |
508 |
} |
509 |
if (c instanceof Deque) { |
510 |
Deque d = (Deque) c; |
511 |
ArrayList descending = new ArrayList(); |
512 |
ArrayList descendingForEachRemaining = new ArrayList(); |
513 |
for (Iterator it = d.descendingIterator(); it.hasNext(); ) |
514 |
descending.add(it.next()); |
515 |
d.descendingIterator().forEachRemaining( |
516 |
e -> descendingForEachRemaining.add(e)); |
517 |
Collections.reverse(descending); |
518 |
Collections.reverse(descendingForEachRemaining); |
519 |
assertEquals(iterated, descending); |
520 |
assertEquals(iterated, descendingForEachRemaining); |
521 |
} |
522 |
} |
523 |
|
524 |
/** |
525 |
* Iterator.forEachRemaining has same behavior as Iterator's |
526 |
* default implementation. |
527 |
*/ |
528 |
public void testForEachRemainingConsistentWithDefaultImplementation() { |
529 |
Collection c = impl.emptyCollection(); |
530 |
if (!testImplementationDetails |
531 |
|| c.getClass() == java.util.LinkedList.class) |
532 |
return; |
533 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
534 |
int n = 1 + rnd.nextInt(3); |
535 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
536 |
ArrayList iterated = new ArrayList(); |
537 |
ArrayList iteratedForEachRemaining = new ArrayList(); |
538 |
Iterator it1 = c.iterator(); |
539 |
Iterator it2 = c.iterator(); |
540 |
assertTrue(it1.hasNext()); |
541 |
assertTrue(it2.hasNext()); |
542 |
c.clear(); |
543 |
Object r1, r2; |
544 |
try { |
545 |
while (it1.hasNext()) iterated.add(it1.next()); |
546 |
r1 = iterated; |
547 |
} catch (ConcurrentModificationException ex) { |
548 |
r1 = ConcurrentModificationException.class; |
549 |
assertFalse(impl.isConcurrent()); |
550 |
} |
551 |
try { |
552 |
it2.forEachRemaining(iteratedForEachRemaining::add); |
553 |
r2 = iteratedForEachRemaining; |
554 |
} catch (ConcurrentModificationException ex) { |
555 |
r2 = ConcurrentModificationException.class; |
556 |
assertFalse(impl.isConcurrent()); |
557 |
} |
558 |
assertEquals(r1, r2); |
559 |
} |
560 |
|
561 |
/** |
562 |
* Calling Iterator#remove() after Iterator#forEachRemaining |
563 |
* should (maybe) remove last element |
564 |
*/ |
565 |
public void testRemoveAfterForEachRemaining() { |
566 |
Collection c = impl.emptyCollection(); |
567 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
568 |
ArrayList copy = new ArrayList(); |
569 |
boolean ordered = c.spliterator().hasCharacteristics(Spliterator.ORDERED); |
570 |
testCollection: { |
571 |
int n = 3 + rnd.nextInt(2); |
572 |
for (int i = 0; i < n; i++) { |
573 |
Object x = impl.makeElement(i); |
574 |
c.add(x); |
575 |
copy.add(x); |
576 |
} |
577 |
Iterator it = c.iterator(); |
578 |
if (ordered) { |
579 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
580 |
assertEquals(impl.makeElement(0), it.next()); |
581 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
582 |
assertEquals(impl.makeElement(1), it.next()); |
583 |
} else { |
584 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
585 |
assertTrue(copy.contains(it.next())); |
586 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
587 |
assertTrue(copy.contains(it.next())); |
588 |
} |
589 |
if (rnd.nextBoolean()) assertTrue(it.hasNext()); |
590 |
it.forEachRemaining( |
591 |
e -> { |
592 |
assertTrue(c.contains(e)); |
593 |
assertTrue(copy.contains(e));}); |
594 |
if (testImplementationDetails) { |
595 |
if (c instanceof java.util.concurrent.ArrayBlockingQueue) { |
596 |
assertIteratorExhausted(it); |
597 |
} else { |
598 |
try { it.remove(); } |
599 |
catch (UnsupportedOperationException ok) { |
600 |
break testCollection; |
601 |
} |
602 |
assertEquals(n - 1, c.size()); |
603 |
if (ordered) { |
604 |
for (int i = 0; i < n - 1; i++) |
605 |
assertTrue(c.contains(impl.makeElement(i))); |
606 |
assertFalse(c.contains(impl.makeElement(n - 1))); |
607 |
} |
608 |
} |
609 |
} |
610 |
} |
611 |
if (c instanceof Deque) { |
612 |
Deque d = (Deque) impl.emptyCollection(); |
613 |
assertTrue(ordered); |
614 |
int n = 3 + rnd.nextInt(2); |
615 |
for (int i = 0; i < n; i++) d.add(impl.makeElement(i)); |
616 |
Iterator it = d.descendingIterator(); |
617 |
assertTrue(it.hasNext()); |
618 |
assertEquals(impl.makeElement(n - 1), it.next()); |
619 |
assertTrue(it.hasNext()); |
620 |
assertEquals(impl.makeElement(n - 2), it.next()); |
621 |
it.forEachRemaining(e -> assertTrue(c.contains(e))); |
622 |
if (testImplementationDetails) { |
623 |
it.remove(); |
624 |
assertEquals(n - 1, d.size()); |
625 |
for (int i = 1; i < n; i++) |
626 |
assertTrue(d.contains(impl.makeElement(i))); |
627 |
assertFalse(d.contains(impl.makeElement(0))); |
628 |
} |
629 |
} |
630 |
} |
631 |
|
632 |
/** |
633 |
* stream().forEach returns elements in the collection |
634 |
*/ |
635 |
public void testStreamForEach() throws Throwable { |
636 |
final Collection c = impl.emptyCollection(); |
637 |
final AtomicLong count = new AtomicLong(0L); |
638 |
final Object x = impl.makeElement(1); |
639 |
final Object y = impl.makeElement(2); |
640 |
final ArrayList found = new ArrayList(); |
641 |
Consumer<Object> spy = o -> found.add(o); |
642 |
c.stream().forEach(spy); |
643 |
assertTrue(found.isEmpty()); |
644 |
|
645 |
assertTrue(c.add(x)); |
646 |
c.stream().forEach(spy); |
647 |
assertEquals(Collections.singletonList(x), found); |
648 |
found.clear(); |
649 |
|
650 |
assertTrue(c.add(y)); |
651 |
c.stream().forEach(spy); |
652 |
assertEquals(2, found.size()); |
653 |
assertTrue(found.contains(x)); |
654 |
assertTrue(found.contains(y)); |
655 |
found.clear(); |
656 |
|
657 |
c.clear(); |
658 |
c.stream().forEach(spy); |
659 |
assertTrue(found.isEmpty()); |
660 |
} |
661 |
|
662 |
public void testStreamForEachConcurrentStressTest() throws Throwable { |
663 |
if (!impl.isConcurrent()) return; |
664 |
final Collection c = impl.emptyCollection(); |
665 |
final long testDurationMillis = timeoutMillis(); |
666 |
final AtomicBoolean done = new AtomicBoolean(false); |
667 |
final Object elt = impl.makeElement(1); |
668 |
final Future<?> f1, f2; |
669 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
670 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
671 |
final CountDownLatch threadsStarted = new CountDownLatch(2); |
672 |
Runnable checkElt = () -> { |
673 |
threadsStarted.countDown(); |
674 |
while (!done.get()) |
675 |
c.stream().forEach(x -> assertSame(x, elt)); }; |
676 |
Runnable addRemove = () -> { |
677 |
threadsStarted.countDown(); |
678 |
while (!done.get()) { |
679 |
assertTrue(c.add(elt)); |
680 |
assertTrue(c.remove(elt)); |
681 |
}}; |
682 |
f1 = pool.submit(checkElt); |
683 |
f2 = pool.submit(addRemove); |
684 |
Thread.sleep(testDurationMillis); |
685 |
} |
686 |
assertNull(f1.get(0L, MILLISECONDS)); |
687 |
assertNull(f2.get(0L, MILLISECONDS)); |
688 |
} |
689 |
|
690 |
/** |
691 |
* collection.forEach returns elements in the collection |
692 |
*/ |
693 |
public void testForEach() throws Throwable { |
694 |
final Collection c = impl.emptyCollection(); |
695 |
final AtomicLong count = new AtomicLong(0L); |
696 |
final Object x = impl.makeElement(1); |
697 |
final Object y = impl.makeElement(2); |
698 |
final ArrayList found = new ArrayList(); |
699 |
Consumer<Object> spy = o -> found.add(o); |
700 |
c.forEach(spy); |
701 |
assertTrue(found.isEmpty()); |
702 |
|
703 |
assertTrue(c.add(x)); |
704 |
c.forEach(spy); |
705 |
assertEquals(Collections.singletonList(x), found); |
706 |
found.clear(); |
707 |
|
708 |
assertTrue(c.add(y)); |
709 |
c.forEach(spy); |
710 |
assertEquals(2, found.size()); |
711 |
assertTrue(found.contains(x)); |
712 |
assertTrue(found.contains(y)); |
713 |
found.clear(); |
714 |
|
715 |
c.clear(); |
716 |
c.forEach(spy); |
717 |
assertTrue(found.isEmpty()); |
718 |
} |
719 |
|
720 |
/** TODO: promote to a common utility */ |
721 |
static <T> T chooseOne(T ... ts) { |
722 |
return ts[ThreadLocalRandom.current().nextInt(ts.length)]; |
723 |
} |
724 |
|
725 |
/** TODO: more random adders and removers */ |
726 |
static <E> Runnable adderRemover(Collection<E> c, E e) { |
727 |
return chooseOne( |
728 |
() -> { |
729 |
assertTrue(c.add(e)); |
730 |
assertTrue(c.contains(e)); |
731 |
assertTrue(c.remove(e)); |
732 |
assertFalse(c.contains(e)); |
733 |
}, |
734 |
() -> { |
735 |
assertTrue(c.add(e)); |
736 |
assertTrue(c.contains(e)); |
737 |
assertTrue(c.removeIf(x -> x == e)); |
738 |
assertFalse(c.contains(e)); |
739 |
}, |
740 |
() -> { |
741 |
assertTrue(c.add(e)); |
742 |
assertTrue(c.contains(e)); |
743 |
for (Iterator it = c.iterator();; ) |
744 |
if (it.next() == e) { |
745 |
try { it.remove(); } |
746 |
catch (UnsupportedOperationException ok) { |
747 |
c.remove(e); |
748 |
} |
749 |
break; |
750 |
} |
751 |
assertFalse(c.contains(e)); |
752 |
}); |
753 |
} |
754 |
|
755 |
/** |
756 |
* Concurrent Spliterators, once exhausted, stay exhausted. |
757 |
*/ |
758 |
public void testStickySpliteratorExhaustion() throws Throwable { |
759 |
if (!impl.isConcurrent()) return; |
760 |
if (!testImplementationDetails) return; |
761 |
final ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
762 |
final Consumer alwaysThrows = e -> { throw new AssertionError(); }; |
763 |
final Collection c = impl.emptyCollection(); |
764 |
final Spliterator s = c.spliterator(); |
765 |
if (rnd.nextBoolean()) { |
766 |
assertFalse(s.tryAdvance(alwaysThrows)); |
767 |
} else { |
768 |
s.forEachRemaining(alwaysThrows); |
769 |
} |
770 |
final Object one = impl.makeElement(1); |
771 |
// Spliterator should not notice added element |
772 |
c.add(one); |
773 |
if (rnd.nextBoolean()) { |
774 |
assertFalse(s.tryAdvance(alwaysThrows)); |
775 |
} else { |
776 |
s.forEachRemaining(alwaysThrows); |
777 |
} |
778 |
} |
779 |
|
780 |
/** |
781 |
* Motley crew of threads concurrently randomly hammer the collection. |
782 |
*/ |
783 |
public void testDetectRaces() throws Throwable { |
784 |
if (!impl.isConcurrent()) return; |
785 |
final ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
786 |
final Collection c = impl.emptyCollection(); |
787 |
final long testDurationMillis |
788 |
= expensiveTests ? LONG_DELAY_MS : timeoutMillis(); |
789 |
final AtomicBoolean done = new AtomicBoolean(false); |
790 |
final Object one = impl.makeElement(1); |
791 |
final Object two = impl.makeElement(2); |
792 |
final Consumer checkSanity = x -> assertTrue(x == one || x == two); |
793 |
final Consumer<Object[]> checkArraySanity = array -> { |
794 |
// assertTrue(array.length <= 2); // duplicates are permitted |
795 |
for (Object x : array) assertTrue(x == one || x == two); |
796 |
}; |
797 |
final Object[] emptyArray = |
798 |
(Object[]) java.lang.reflect.Array.newInstance(one.getClass(), 0); |
799 |
final List<Future<?>> futures; |
800 |
final Phaser threadsStarted = new Phaser(1); // register this thread |
801 |
final Runnable[] frobbers = { |
802 |
() -> c.forEach(checkSanity), |
803 |
() -> c.stream().forEach(checkSanity), |
804 |
() -> c.parallelStream().forEach(checkSanity), |
805 |
() -> c.spliterator().trySplit(), |
806 |
() -> { |
807 |
Spliterator s = c.spliterator(); |
808 |
s.tryAdvance(checkSanity); |
809 |
s.trySplit(); |
810 |
}, |
811 |
() -> { |
812 |
Spliterator s = c.spliterator(); |
813 |
do {} while (s.tryAdvance(checkSanity)); |
814 |
}, |
815 |
() -> { for (Object x : c) checkSanity.accept(x); }, |
816 |
() -> checkArraySanity.accept(c.toArray()), |
817 |
() -> checkArraySanity.accept(c.toArray(emptyArray)), |
818 |
() -> { |
819 |
Object[] a = new Object[5]; |
820 |
Object three = impl.makeElement(3); |
821 |
Arrays.fill(a, 0, a.length, three); |
822 |
Object[] x = c.toArray(a); |
823 |
if (x == a) |
824 |
for (int i = 0; i < a.length && a[i] != null; i++) |
825 |
checkSanity.accept(a[i]); |
826 |
// A careful reading of the spec does not support: |
827 |
// for (i++; i < a.length; i++) assertSame(three, a[i]); |
828 |
else |
829 |
checkArraySanity.accept(x); |
830 |
}, |
831 |
adderRemover(c, one), |
832 |
adderRemover(c, two), |
833 |
}; |
834 |
final List<Runnable> tasks = |
835 |
Arrays.stream(frobbers) |
836 |
.filter(task -> rnd.nextBoolean()) // random subset |
837 |
.map(task -> (Runnable) () -> { |
838 |
threadsStarted.arriveAndAwaitAdvance(); |
839 |
while (!done.get()) |
840 |
task.run(); |
841 |
}) |
842 |
.collect(Collectors.toList()); |
843 |
final ExecutorService pool = Executors.newCachedThreadPool(); |
844 |
try (PoolCleaner cleaner = cleaner(pool, done)) { |
845 |
threadsStarted.bulkRegister(tasks.size()); |
846 |
futures = tasks.stream() |
847 |
.map(pool::submit) |
848 |
.collect(Collectors.toList()); |
849 |
threadsStarted.arriveAndDeregister(); |
850 |
Thread.sleep(testDurationMillis); |
851 |
} |
852 |
for (Future future : futures) |
853 |
assertNull(future.get(0L, MILLISECONDS)); |
854 |
} |
855 |
|
856 |
/** |
857 |
* Spliterators are either IMMUTABLE or truly late-binding or, if |
858 |
* concurrent, use the same "late-binding style" of returning |
859 |
* elements added between creation and first use. |
860 |
*/ |
861 |
public void testLateBindingStyle() { |
862 |
if (!testImplementationDetails) return; |
863 |
if (impl.klazz() == ArrayList.class) return; // for jdk8 |
864 |
// Immutable (snapshot) spliterators are exempt |
865 |
if (impl.emptyCollection().spliterator() |
866 |
.hasCharacteristics(Spliterator.IMMUTABLE)) |
867 |
return; |
868 |
final Object one = impl.makeElement(1); |
869 |
{ |
870 |
final Collection c = impl.emptyCollection(); |
871 |
final Spliterator split = c.spliterator(); |
872 |
c.add(one); |
873 |
assertTrue(split.tryAdvance(e -> { assertSame(e, one); })); |
874 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
875 |
assertTrue(c.contains(one)); |
876 |
} |
877 |
{ |
878 |
final AtomicLong count = new AtomicLong(0); |
879 |
final Collection c = impl.emptyCollection(); |
880 |
final Spliterator split = c.spliterator(); |
881 |
c.add(one); |
882 |
split.forEachRemaining( |
883 |
e -> { assertSame(e, one); count.getAndIncrement(); }); |
884 |
assertEquals(1L, count.get()); |
885 |
assertFalse(split.tryAdvance(e -> { throw new AssertionError(); })); |
886 |
assertTrue(c.contains(one)); |
887 |
} |
888 |
} |
889 |
|
890 |
/** |
891 |
* Spliterator.getComparator throws IllegalStateException iff the |
892 |
* spliterator does not report SORTED. |
893 |
*/ |
894 |
public void testGetComparator_IllegalStateException() { |
895 |
Collection c = impl.emptyCollection(); |
896 |
Spliterator s = c.spliterator(); |
897 |
boolean reportsSorted = s.hasCharacteristics(Spliterator.SORTED); |
898 |
try { |
899 |
s.getComparator(); |
900 |
assertTrue(reportsSorted); |
901 |
} catch (IllegalStateException ex) { |
902 |
assertFalse(reportsSorted); |
903 |
} |
904 |
} |
905 |
|
906 |
public void testCollectionCopies() throws Exception { |
907 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
908 |
Collection c = impl.emptyCollection(); |
909 |
for (int n = rnd.nextInt(4); n--> 0; ) |
910 |
c.add(impl.makeElement(rnd.nextInt())); |
911 |
assertEquals(c, c); |
912 |
if (c instanceof List) |
913 |
assertCollectionsEquals(c, new ArrayList(c)); |
914 |
else if (c instanceof Set) |
915 |
assertCollectionsEquals(c, new HashSet(c)); |
916 |
else if (c instanceof Deque) |
917 |
assertCollectionsEquivalent(c, new ArrayDeque(c)); |
918 |
|
919 |
Collection clone = cloneableClone(c); |
920 |
if (clone != null) { |
921 |
assertSame(c.getClass(), clone.getClass()); |
922 |
assertCollectionsEquivalent(c, clone); |
923 |
} |
924 |
try { |
925 |
Collection serialClone = serialClonePossiblyFailing(c); |
926 |
assertSame(c.getClass(), serialClone.getClass()); |
927 |
assertCollectionsEquivalent(c, serialClone); |
928 |
} catch (java.io.NotSerializableException acceptable) {} |
929 |
} |
930 |
|
931 |
public void testReplaceAllIsNotStructuralModification() { |
932 |
Collection c = impl.emptyCollection(); |
933 |
if (!(c instanceof List)) |
934 |
return; |
935 |
List list = (List) c; |
936 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
937 |
for (int n = rnd.nextInt(2, 10); n--> 0; ) |
938 |
list.add(impl.makeElement(rnd.nextInt())); |
939 |
ArrayList copy = new ArrayList(list); |
940 |
int size = list.size(), half = size / 2; |
941 |
Iterator it = list.iterator(); |
942 |
for (int i = 0; i < half; i++) |
943 |
assertEquals(it.next(), copy.get(i)); |
944 |
list.replaceAll(n -> n); |
945 |
// ConcurrentModificationException must not be thrown here. |
946 |
for (int i = half; i < size; i++) |
947 |
assertEquals(it.next(), copy.get(i)); |
948 |
} |
949 |
|
950 |
// public void testCollection8DebugFail() { |
951 |
// fail(impl.klazz().getSimpleName()); |
952 |
// } |
953 |
} |