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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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* Other contributors include Andrew Wright, Jeffrey Hayes, |
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* Pat Fisher, Mike Judd. |
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*/ |
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|
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import java.util.Arrays; |
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import java.util.Collection; |
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import java.util.Iterator; |
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import java.util.NoSuchElementException; |
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import java.util.Queue; |
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import java.util.concurrent.ConcurrentLinkedQueue; |
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|
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import junit.framework.Test; |
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|
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public class ConcurrentLinkedQueueTest extends JSR166TestCase { |
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|
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public static void main(String[] args) { |
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main(suite(), args); |
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} |
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|
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public static Test suite() { |
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class Implementation implements CollectionImplementation { |
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public Class<?> klazz() { return ConcurrentLinkedQueue.class; } |
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public Collection emptyCollection() { return new ConcurrentLinkedQueue(); } |
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public Object makeElement(int i) { return JSR166TestCase.itemFor(i); } |
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public boolean isConcurrent() { return true; } |
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public boolean permitsNulls() { return false; } |
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} |
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return newTestSuite(ConcurrentLinkedQueueTest.class, |
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CollectionTest.testSuite(new Implementation())); |
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} |
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|
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/** |
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* Returns a new queue of given size containing consecutive |
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* Items 0 ... n - 1. |
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*/ |
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private static ConcurrentLinkedQueue<Item> populatedQueue(int n) { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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assertTrue(q.isEmpty()); |
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for (int i = 0; i < n; ++i) |
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mustOffer(q, i); |
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assertFalse(q.isEmpty()); |
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mustEqual(n, q.size()); |
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mustEqual(0, q.peek()); |
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return q; |
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} |
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|
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/** |
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* new queue is empty |
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*/ |
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public void testConstructor1() { |
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mustEqual(0, new ConcurrentLinkedQueue<Item>().size()); |
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} |
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|
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/** |
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* Initializing from null Collection throws NPE |
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*/ |
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public void testConstructor3() { |
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try { |
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new ConcurrentLinkedQueue<Item>((Collection<Item>)null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* Initializing from Collection of null elements throws NPE |
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*/ |
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public void testConstructor4() { |
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try { |
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new ConcurrentLinkedQueue<Item>(Arrays.asList(new Item[SIZE])); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* Initializing from Collection with some null elements throws NPE |
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*/ |
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public void testConstructor5() { |
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Item[] items = new Item[2]; |
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items[0] = zero; |
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try { |
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new ConcurrentLinkedQueue<Item>(Arrays.asList(items)); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* Queue contains all elements of collection used to initialize |
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*/ |
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public void testConstructor6() { |
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Item[] items = defaultItems; |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(Arrays.asList(items)); |
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for (int i = 0; i < SIZE; ++i) |
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mustEqual(items[i], q.poll()); |
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} |
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|
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/** |
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* isEmpty is true before add, false after |
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*/ |
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public void testEmpty() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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assertTrue(q.isEmpty()); |
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q.add(one); |
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assertFalse(q.isEmpty()); |
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q.add(two); |
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q.remove(); |
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q.remove(); |
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assertTrue(q.isEmpty()); |
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} |
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|
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/** |
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* size changes when elements added and removed |
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*/ |
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public void testSize() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(SIZE - i, q.size()); |
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q.remove(); |
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} |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.size()); |
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mustAdd(q, i); |
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} |
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} |
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|
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/** |
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* offer(null) throws NPE |
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*/ |
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public void testOfferNull() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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try { |
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q.offer(null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* add(null) throws NPE |
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*/ |
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public void testAddNull() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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try { |
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q.add(null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* Offer returns true |
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*/ |
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public void testOffer() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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assertTrue(q.offer(zero)); |
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assertTrue(q.offer(one)); |
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} |
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|
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/** |
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* add returns true |
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*/ |
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public void testAdd() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.size()); |
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mustAdd(q, i); |
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} |
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} |
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|
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/** |
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* addAll(null) throws NullPointerException |
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*/ |
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public void testAddAll1() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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try { |
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q.addAll(null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* addAll(this) throws IllegalArgumentException |
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*/ |
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public void testAddAllSelf() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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try { |
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q.addAll(q); |
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shouldThrow(); |
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} catch (IllegalArgumentException success) {} |
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} |
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|
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/** |
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* addAll of a collection with null elements throws NullPointerException |
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*/ |
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public void testAddAll2() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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try { |
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q.addAll(Arrays.asList(new Item[SIZE])); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* addAll of a collection with any null elements throws NPE after |
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* possibly adding some elements |
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*/ |
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public void testAddAll3() { |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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Item[] items = new Item[2]; |
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items[0] = zero; |
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try { |
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q.addAll(Arrays.asList(items)); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* Queue contains all elements, in traversal order, of successful addAll |
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*/ |
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public void testAddAll5() { |
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Item[] empty = new Item[0]; |
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Item[] items = defaultItems; |
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ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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assertFalse(q.addAll(Arrays.asList(empty))); |
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assertTrue(q.addAll(Arrays.asList(items))); |
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for (int i = 0; i < SIZE; ++i) |
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mustEqual(items[i], q.poll()); |
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} |
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|
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/** |
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* poll succeeds unless empty |
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*/ |
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public void testPoll() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.poll()); |
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} |
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assertNull(q.poll()); |
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} |
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|
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/** |
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* peek returns next element, or null if empty |
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*/ |
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public void testPeek() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.peek()); |
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mustEqual(i, q.poll()); |
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assertTrue(q.peek() == null || |
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!q.peek().equals(i)); |
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} |
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assertNull(q.peek()); |
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} |
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|
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/** |
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* element returns next element, or throws NSEE if empty |
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*/ |
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public void testElement() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.element()); |
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mustEqual(i, q.poll()); |
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} |
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try { |
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q.element(); |
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shouldThrow(); |
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} catch (NoSuchElementException success) {} |
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} |
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|
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/** |
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* remove removes next element, or throws NSEE if empty |
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*/ |
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public void testRemove() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustEqual(i, q.remove()); |
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} |
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try { |
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q.remove(); |
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shouldThrow(); |
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} catch (NoSuchElementException success) {} |
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} |
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|
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/** |
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* remove(x) removes x and returns true if present |
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*/ |
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public void testRemoveElement() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 1; i < SIZE; i += 2) { |
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mustContain(q, i); |
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mustRemove(q, i); |
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mustNotContain(q, i); |
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mustContain(q, i - 1); |
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} |
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for (int i = 0; i < SIZE; i += 2) { |
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mustContain(q, i); |
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mustRemove(q, i); |
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mustNotContain(q, i); |
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mustNotRemove(q, i + 1); |
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mustNotContain(q, i + 1); |
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} |
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assertTrue(q.isEmpty()); |
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} |
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|
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/** |
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* contains(x) reports true when elements added but not yet removed |
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*/ |
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public void testContains() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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mustContain(q, i); |
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q.poll(); |
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mustNotContain(q, i); |
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} |
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} |
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|
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/** |
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* clear removes all elements |
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*/ |
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public void testClear() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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q.clear(); |
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assertTrue(q.isEmpty()); |
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mustEqual(0, q.size()); |
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q.add(one); |
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assertFalse(q.isEmpty()); |
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q.clear(); |
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assertTrue(q.isEmpty()); |
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} |
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|
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/** |
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* containsAll(c) is true when c contains a subset of elements |
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*/ |
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public void testContainsAll() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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ConcurrentLinkedQueue<Item> p = new ConcurrentLinkedQueue<>(); |
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for (int i = 0; i < SIZE; ++i) { |
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assertTrue(q.containsAll(p)); |
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assertFalse(p.containsAll(q)); |
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mustAdd(p, i); |
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} |
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assertTrue(p.containsAll(q)); |
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} |
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|
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/** |
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* retainAll(c) retains only those elements of c and reports true if change |
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*/ |
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public void testRetainAll() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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ConcurrentLinkedQueue<Item> p = populatedQueue(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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boolean changed = q.retainAll(p); |
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if (i == 0) |
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assertFalse(changed); |
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else |
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assertTrue(changed); |
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|
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assertTrue(q.containsAll(p)); |
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mustEqual(SIZE - i, q.size()); |
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p.remove(); |
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} |
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} |
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|
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/** |
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* removeAll(c) removes only those elements of c and reports true if changed |
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*/ |
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public void testRemoveAll() { |
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for (int i = 1; i < SIZE; ++i) { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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ConcurrentLinkedQueue<Item> p = populatedQueue(i); |
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assertTrue(q.removeAll(p)); |
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mustEqual(SIZE - i, q.size()); |
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for (int j = 0; j < i; ++j) { |
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Item x = p.remove(); |
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assertFalse(q.contains(x)); |
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} |
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} |
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} |
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|
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/** |
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* toArray contains all elements in FIFO order |
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*/ |
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public void testToArray() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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Object[] a = q.toArray(); |
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assertSame(Object[].class, a.getClass()); |
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for (Object o : a) |
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assertSame(o, q.poll()); |
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assertTrue(q.isEmpty()); |
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} |
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|
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/** |
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* toArray(a) contains all elements in FIFO order |
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*/ |
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public void testToArray2() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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Item[] items = new Item[SIZE]; |
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Item[] array = q.toArray(items); |
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assertSame(items, array); |
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for (Item o : items) |
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assertSame(o, q.poll()); |
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assertTrue(q.isEmpty()); |
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} |
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|
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/** |
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* toArray(null) throws NullPointerException |
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*/ |
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public void testToArray_NullArg() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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try { |
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q.toArray((Object[])null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* toArray(incompatible array type) throws ArrayStoreException |
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*/ |
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@SuppressWarnings("CollectionToArraySafeParameter") |
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public void testToArray_incompatibleArrayType() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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try { |
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q.toArray(new String[10]); |
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shouldThrow(); |
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} catch (ArrayStoreException success) {} |
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} |
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|
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/** |
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* iterator iterates through all elements |
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*/ |
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public void testIterator() { |
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ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
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Iterator<? extends Item> it = q.iterator(); |
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int i; |
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for (i = 0; it.hasNext(); i++) |
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mustContain(q, it.next()); |
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mustEqual(i, SIZE); |
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assertIteratorExhausted(it); |
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} |
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|
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/** |
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* iterator of empty collection has no elements |
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*/ |
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public void testEmptyIterator() { |
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assertIteratorExhausted(new ConcurrentLinkedQueue<>().iterator()); |
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} |
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|
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/** |
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* iterator ordering is FIFO |
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*/ |
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public void testIteratorOrdering() { |
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final ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
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q.add(one); |
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q.add(two); |
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q.add(three); |
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|
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int k = 0; |
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for (Iterator<? extends Item> it = q.iterator(); it.hasNext();) { |
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mustEqual(++k, it.next()); |
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} |
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|
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mustEqual(3, k); |
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} |
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|
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/** |
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* Modifications do not cause iterators to fail |
468 |
*/ |
469 |
public void testWeaklyConsistentIteration() { |
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final ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
471 |
q.add(one); |
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q.add(two); |
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q.add(three); |
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|
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for (Iterator<? extends Item> it = q.iterator(); it.hasNext();) { |
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q.remove(); |
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it.next(); |
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} |
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|
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mustEqual(0, q.size()); |
481 |
} |
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|
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/** |
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* iterator.remove removes current element |
485 |
*/ |
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public void testIteratorRemove() { |
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final ConcurrentLinkedQueue<Item> q = new ConcurrentLinkedQueue<>(); |
488 |
q.add(one); |
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q.add(two); |
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q.add(three); |
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Iterator<? extends Item> it = q.iterator(); |
492 |
it.next(); |
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it.remove(); |
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it = q.iterator(); |
495 |
assertSame(it.next(), two); |
496 |
assertSame(it.next(), three); |
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assertFalse(it.hasNext()); |
498 |
} |
499 |
|
500 |
/** |
501 |
* toString contains toStrings of elements |
502 |
*/ |
503 |
public void testToString() { |
504 |
ConcurrentLinkedQueue<Item> q = populatedQueue(SIZE); |
505 |
String s = q.toString(); |
506 |
for (int i = 0; i < SIZE; ++i) { |
507 |
assertTrue(s.contains(String.valueOf(i))); |
508 |
} |
509 |
} |
510 |
|
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/** |
512 |
* A deserialized/reserialized queue has same elements in same order |
513 |
*/ |
514 |
public void testSerialization() throws Exception { |
515 |
Queue<Item> x = populatedQueue(SIZE); |
516 |
Queue<Item> y = serialClone(x); |
517 |
|
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assertNotSame(x, y); |
519 |
mustEqual(x.size(), y.size()); |
520 |
mustEqual(x.toString(), y.toString()); |
521 |
assertTrue(Arrays.equals(x.toArray(), y.toArray())); |
522 |
while (!x.isEmpty()) { |
523 |
assertFalse(y.isEmpty()); |
524 |
mustEqual(x.remove(), y.remove()); |
525 |
} |
526 |
assertTrue(y.isEmpty()); |
527 |
} |
528 |
|
529 |
/** |
530 |
* remove(null), contains(null) always return false |
531 |
*/ |
532 |
public void testNeverContainsNull() { |
533 |
Collection<?>[] qs = { |
534 |
new ConcurrentLinkedQueue<>(), |
535 |
populatedQueue(2), |
536 |
}; |
537 |
|
538 |
for (Collection<?> q : qs) { |
539 |
assertFalse(q.contains(null)); |
540 |
assertFalse(q.remove(null)); |
541 |
} |
542 |
} |
543 |
} |