--- jsr166/src/test/tck/PriorityQueueTest.java	2003/09/07 20:39:11	1.2
+++ jsr166/src/test/tck/PriorityQueueTest.java	2018/05/28 21:19:50	1.47
@@ -1,123 +1,151 @@
 /*
- * Written by members of JCP JSR-166 Expert Group and released to the
- * public domain. Use, modify, and redistribute this code in any way
- * without acknowledgement. Other contributors include Andrew Wright,
- * Jeffrey Hayes, Pat Fischer, Mike Judd.
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ * Other contributors include Andrew Wright, Jeffrey Hayes,
+ * Pat Fisher, Mike Judd.
  */
 
-import junit.framework.*;
-import java.util.*;
-import java.util.concurrent.*;
-import java.io.*;
-
-public class PriorityQueueTest extends TestCase {
-
-    private static final int N = 10;
-    private static final long SHORT_DELAY_MS = 100; 
-    private static final long MEDIUM_DELAY_MS = 1000;
-    private static final long LONG_DELAY_MS = 10000; 
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.PriorityQueue;
+import java.util.Queue;
 
+import junit.framework.Test;
+
+public class PriorityQueueTest extends JSR166TestCase {
     public static void main(String[] args) {
-	junit.textui.TestRunner.run (suite());	
+        main(suite(), args);
     }
-
     public static Test suite() {
-	return new TestSuite(PriorityQueueTest.class);
+        class Implementation implements CollectionImplementation {
+            public Class<?> klazz() { return PriorityQueue.class; }
+            public Collection emptyCollection() { return new PriorityQueue(); }
+            public Object makeElement(int i) { return i; }
+            public boolean isConcurrent() { return false; }
+            public boolean permitsNulls() { return false; }
+        }
+        class ComparatorImplementation implements CollectionImplementation {
+            public Class<?> klazz() { return PriorityQueue.class; }
+            public Collection emptyCollection() {
+                return new PriorityQueue(new MyReverseComparator());
+            }
+            public Object makeElement(int i) { return i; }
+            public boolean isConcurrent() { return false; }
+            public boolean permitsNulls() { return false; }
+        }
+        return newTestSuite(
+            PriorityQueueTest.class,
+            CollectionTest.testSuite(new Implementation()),
+            CollectionTest.testSuite(new ComparatorImplementation()));
     }
 
-    static class MyReverseComparator implements Comparator { 
+    static class MyReverseComparator implements Comparator, java.io.Serializable {
         public int compare(Object x, Object y) {
-            int i = ((Integer)x).intValue();
-            int j = ((Integer)y).intValue();
-            if (i < j) return 1;
-            if (i > j) return -1;
-            return 0;
+            return ((Comparable)y).compareTo(x);
         }
     }
 
-
     /**
-     * Create a queue of given size containing consecutive
-     * Integers 0 ... n.
+     * Returns a new queue of given size containing consecutive
+     * Integers 0 ... n - 1.
      */
-    private PriorityQueue fullQueue(int n) {
-        PriorityQueue q = new PriorityQueue(n);
+    private static PriorityQueue<Integer> populatedQueue(int n) {
+        PriorityQueue<Integer> q = new PriorityQueue<>(n);
         assertTrue(q.isEmpty());
-	for(int i = n-1; i >= 0; i-=2)
-	    assertTrue(q.offer(new Integer(i)));
-	for(int i = (n & 1); i < n; i+=2)
-	    assertTrue(q.offer(new Integer(i)));
+        for (int i = n - 1; i >= 0; i -= 2)
+            assertTrue(q.offer(new Integer(i)));
+        for (int i = (n & 1); i < n; i += 2)
+            assertTrue(q.offer(new Integer(i)));
         assertFalse(q.isEmpty());
-	assertEquals(n, q.size());
+        assertEquals(n, q.size());
+        assertEquals((Integer) 0, q.peek());
         return q;
     }
- 
-    public void testConstructor1(){
-        assertEquals(0, new PriorityQueue(N).size());
+
+    /**
+     * A new queue has unbounded capacity
+     */
+    public void testConstructor1() {
+        assertEquals(0, new PriorityQueue(SIZE).size());
     }
 
-    public void testConstructor2(){
+    /**
+     * Constructor throws IllegalArgumentException if capacity argument nonpositive
+     */
+    public void testConstructor2() {
         try {
-            PriorityQueue q = new PriorityQueue(0);
-            fail("Cannot make zero-sized");
-        }
-        catch (IllegalArgumentException success) {}
+            new PriorityQueue(0);
+            shouldThrow();
+        } catch (IllegalArgumentException success) {}
     }
 
+    /**
+     * Initializing from null Collection throws NPE
+     */
     public void testConstructor3() {
-
         try {
-            PriorityQueue q = new PriorityQueue((Collection)null);
-            fail("Cannot make from null collection");
-        }
-        catch (NullPointerException success) {}
+            new PriorityQueue((Collection)null);
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor4(){
+    /**
+     * Initializing from Collection of null elements throws NPE
+     */
+    public void testConstructor4() {
         try {
-            Integer[] ints = new Integer[N];
-            PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
-            fail("Cannot make with null elements");
-        }
-        catch (NullPointerException success) {}
+            new PriorityQueue(Arrays.asList(new Integer[SIZE]));
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor5(){
-        try {
-            Integer[] ints = new Integer[N];
-            for (int i = 0; i < N-1; ++i)
-                ints[i] = new Integer(i);
-            PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
-            fail("Cannot make with null elements");
-        }
-        catch (NullPointerException success) {}
+    /**
+     * Initializing from Collection with some null elements throws NPE
+     */
+    public void testConstructor5() {
+        Integer[] ints = new Integer[SIZE];
+        for (int i = 0; i < SIZE - 1; ++i)
+            ints[i] = new Integer(i);
+        try {
+            new PriorityQueue(Arrays.asList(ints));
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor6(){
-        try {
-            Integer[] ints = new Integer[N];
-            for (int i = 0; i < N; ++i)
-                ints[i] = new Integer(i);
-            PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
-            for (int i = 0; i < N; ++i)
-                assertEquals(ints[i], q.poll());
-        }
-        finally {}
+    /**
+     * Queue contains all elements of collection used to initialize
+     */
+    public void testConstructor6() {
+        Integer[] ints = new Integer[SIZE];
+        for (int i = 0; i < SIZE; ++i)
+            ints[i] = new Integer(i);
+        PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(ints[i], q.poll());
     }
 
-    public void testConstructor7(){
-        try {
-            PriorityQueue q = new PriorityQueue(N, new MyReverseComparator());
-            Integer[] ints = new Integer[N];
-            for (int i = 0; i < N; ++i)
-                ints[i] = new Integer(i);
-            q.addAll(Arrays.asList(ints));
-            for (int i = N-1; i >= 0; --i)
-                assertEquals(ints[i], q.poll());
-        }
-        finally {}
+    /**
+     * The comparator used in constructor is used
+     */
+    public void testConstructor7() {
+        MyReverseComparator cmp = new MyReverseComparator();
+        PriorityQueue q = new PriorityQueue(SIZE, cmp);
+        assertEquals(cmp, q.comparator());
+        Integer[] ints = new Integer[SIZE];
+        for (int i = 0; i < SIZE; ++i)
+            ints[i] = new Integer(i);
+        q.addAll(Arrays.asList(ints));
+        for (int i = SIZE - 1; i >= 0; --i)
+            assertEquals(ints[i], q.poll());
     }
 
+    /**
+     * isEmpty is true before add, false after
+     */
     public void testEmpty() {
         PriorityQueue q = new PriorityQueue(2);
         assertTrue(q.isEmpty());
@@ -129,162 +157,222 @@ public class PriorityQueueTest extends T
         assertTrue(q.isEmpty());
     }
 
+    /**
+     * size changes when elements added and removed
+     */
     public void testSize() {
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
-            assertEquals(N-i, q.size());
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(SIZE - i, q.size());
             q.remove();
         }
-        for (int i = 0; i < N; ++i) {
+        for (int i = 0; i < SIZE; ++i) {
             assertEquals(i, q.size());
             q.add(new Integer(i));
         }
     }
 
-    public void testOfferNull(){
-	try {
-            PriorityQueue q = new PriorityQueue(1);
+    /**
+     * offer(null) throws NPE
+     */
+    public void testOfferNull() {
+        PriorityQueue q = new PriorityQueue(1);
+        try {
             q.offer(null);
-            fail("should throw NPE");
-        } catch (NullPointerException success) { }   
+            shouldThrow();
+        } catch (NullPointerException success) {}
+    }
+
+    /**
+     * add(null) throws NPE
+     */
+    public void testAddNull() {
+        PriorityQueue q = new PriorityQueue(1);
+        try {
+            q.add(null);
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
+    /**
+     * Offer of comparable element succeeds
+     */
     public void testOffer() {
         PriorityQueue q = new PriorityQueue(1);
-        assertTrue(q.offer(new Integer(0)));
-        assertTrue(q.offer(new Integer(1)));
+        assertTrue(q.offer(zero));
+        assertTrue(q.offer(one));
     }
 
+    /**
+     * Offer of non-Comparable throws CCE
+     */
     public void testOfferNonComparable() {
+        PriorityQueue q = new PriorityQueue(1);
         try {
-            PriorityQueue q = new PriorityQueue(1);
-            q.offer(new Object());
-            q.offer(new Object());
             q.offer(new Object());
-            fail("should throw CCE");
+            shouldThrow();
+        } catch (ClassCastException success) {
+            assertTrue(q.isEmpty());
+            assertEquals(0, q.size());
+            assertNull(q.poll());
         }
-        catch(ClassCastException success) {}
     }
 
-    public void testAdd(){
-        PriorityQueue q = new PriorityQueue(N);
-        for (int i = 0; i < N; ++i) {
+    /**
+     * add of comparable succeeds
+     */
+    public void testAdd() {
+        PriorityQueue q = new PriorityQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
             assertEquals(i, q.size());
             assertTrue(q.add(new Integer(i)));
         }
     }
 
-    public void testAddAll1(){
+    /**
+     * addAll(null) throws NPE
+     */
+    public void testAddAll1() {
+        PriorityQueue q = new PriorityQueue(1);
         try {
-            PriorityQueue q = new PriorityQueue(1);
             q.addAll(null);
-            fail("Cannot add null collection");
-        }
-        catch (NullPointerException success) {}
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
-    public void testAddAll2(){
+
+    /**
+     * addAll of a collection with null elements throws NPE
+     */
+    public void testAddAll2() {
+        PriorityQueue q = new PriorityQueue(SIZE);
         try {
-            PriorityQueue q = new PriorityQueue(N);
-            Integer[] ints = new Integer[N];
-            q.addAll(Arrays.asList(ints));
-            fail("Cannot add null elements");
-        }
-        catch (NullPointerException success) {}
+            q.addAll(Arrays.asList(new Integer[SIZE]));
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
-    public void testAddAll3(){
+
+    /**
+     * addAll of a collection with any null elements throws NPE after
+     * possibly adding some elements
+     */
+    public void testAddAll3() {
+        PriorityQueue q = new PriorityQueue(SIZE);
+        Integer[] ints = new Integer[SIZE];
+        for (int i = 0; i < SIZE - 1; ++i)
+            ints[i] = new Integer(i);
         try {
-            PriorityQueue q = new PriorityQueue(N);
-            Integer[] ints = new Integer[N];
-            for (int i = 0; i < N-1; ++i)
-                ints[i] = new Integer(i);
             q.addAll(Arrays.asList(ints));
-            fail("Cannot add null elements");
-        }
-        catch (NullPointerException success) {}
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testAddAll5(){
-        try {
-            Integer[] empty = new Integer[0];
-            Integer[] ints = new Integer[N];
-            for (int i = 0; i < N; ++i)
-                ints[i] = new Integer(N-1-i);
-            PriorityQueue q = new PriorityQueue(N);
-            assertFalse(q.addAll(Arrays.asList(empty)));
-            assertTrue(q.addAll(Arrays.asList(ints)));
-            for (int i = 0; i < N; ++i)
-                assertEquals(new Integer(i), q.poll());
-        }
-        finally {}
+    /**
+     * Queue contains all elements of successful addAll
+     */
+    public void testAddAll5() {
+        Integer[] empty = new Integer[0];
+        Integer[] ints = new Integer[SIZE];
+        for (int i = 0; i < SIZE; ++i)
+            ints[i] = new Integer(SIZE - 1 - i);
+        PriorityQueue q = new PriorityQueue(SIZE);
+        assertFalse(q.addAll(Arrays.asList(empty)));
+        assertTrue(q.addAll(Arrays.asList(ints)));
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(new Integer(i), q.poll());
     }
 
-    public void testPoll(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
-            assertEquals(i, ((Integer)q.poll()).intValue());
+    /**
+     * poll succeeds unless empty
+     */
+    public void testPoll() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.poll());
         }
-	assertNull(q.poll());
+        assertNull(q.poll());
     }
 
-    public void testPeek(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
-            assertEquals(i, ((Integer)q.peek()).intValue());
-            q.poll();
+    /**
+     * peek returns next element, or null if empty
+     */
+    public void testPeek() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.peek());
+            assertEquals(i, q.poll());
             assertTrue(q.peek() == null ||
-                       i != ((Integer)q.peek()).intValue());
+                       !q.peek().equals(i));
         }
-	assertNull(q.peek());
+        assertNull(q.peek());
     }
 
-    public void testElement(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
-            assertEquals(i, ((Integer)q.element()).intValue());
-            q.poll();
+    /**
+     * element returns next element, or throws NSEE if empty
+     */
+    public void testElement() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.element());
+            assertEquals(i, q.poll());
         }
         try {
             q.element();
-            fail("no such element");
-        }
-        catch (NoSuchElementException success) {}
+            shouldThrow();
+        } catch (NoSuchElementException success) {}
     }
 
-    public void testRemove(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
-            assertEquals(i, ((Integer)q.remove()).intValue());
+    /**
+     * remove removes next element, or throws NSEE if empty
+     */
+    public void testRemove() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.remove());
         }
         try {
             q.remove();
-            fail("remove should throw");
-        } catch (NoSuchElementException success){
-	}   
+            shouldThrow();
+        } catch (NoSuchElementException success) {}
     }
 
-    public void testRemoveElement(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 1; i < N; i+=2) {
-            assertTrue(q.remove(new Integer(i)));
-        }
-        for (int i = 0; i < N; i+=2) {
-            assertTrue(q.remove(new Integer(i)));
-            assertFalse(q.remove(new Integer(i+1)));
+    /**
+     * remove(x) removes x and returns true if present
+     */
+    public void testRemoveElement() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 1; i < SIZE; i += 2) {
+            assertTrue(q.contains(i));
+            assertTrue(q.remove(i));
+            assertFalse(q.contains(i));
+            assertTrue(q.contains(i - 1));
+        }
+        for (int i = 0; i < SIZE; i += 2) {
+            assertTrue(q.contains(i));
+            assertTrue(q.remove(i));
+            assertFalse(q.contains(i));
+            assertFalse(q.remove(i + 1));
+            assertFalse(q.contains(i + 1));
         }
         assertTrue(q.isEmpty());
     }
-	
-    public void testContains(){
-        PriorityQueue q = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
+
+    /**
+     * contains(x) reports true when elements added but not yet removed
+     */
+    public void testContains() {
+        PriorityQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
             assertTrue(q.contains(new Integer(i)));
             q.poll();
             assertFalse(q.contains(new Integer(i)));
         }
     }
 
-    public void testClear(){
-        PriorityQueue q = fullQueue(N);
+    /**
+     * clear removes all elements
+     */
+    public void testClear() {
+        PriorityQueue q = populatedQueue(SIZE);
         q.clear();
         assertTrue(q.isEmpty());
         assertEquals(0, q.size());
@@ -294,10 +382,13 @@ public class PriorityQueueTest extends T
         assertTrue(q.isEmpty());
     }
 
-    public void testContainsAll(){
-        PriorityQueue q = fullQueue(N);
-        PriorityQueue p = new PriorityQueue(N);
-        for (int i = 0; i < N; ++i) {
+    /**
+     * containsAll(c) is true when c contains a subset of elements
+     */
+    public void testContainsAll() {
+        PriorityQueue q = populatedQueue(SIZE);
+        PriorityQueue p = new PriorityQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
             assertTrue(q.containsAll(p));
             assertFalse(p.containsAll(q));
             p.add(new Integer(i));
@@ -305,10 +396,13 @@ public class PriorityQueueTest extends T
         assertTrue(p.containsAll(q));
     }
 
-    public void testRetainAll(){
-        PriorityQueue q = fullQueue(N);
-        PriorityQueue p = fullQueue(N);
-        for (int i = 0; i < N; ++i) {
+    /**
+     * retainAll(c) retains only those elements of c and reports true if changed
+     */
+    public void testRetainAll() {
+        PriorityQueue q = populatedQueue(SIZE);
+        PriorityQueue p = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
             boolean changed = q.retainAll(p);
             if (i == 0)
                 assertFalse(changed);
@@ -316,56 +410,79 @@ public class PriorityQueueTest extends T
                 assertTrue(changed);
 
             assertTrue(q.containsAll(p));
-            assertEquals(N-i, q.size());
+            assertEquals(SIZE - i, q.size());
             p.remove();
         }
     }
 
-    public void testRemoveAll(){
-        for (int i = 1; i < N; ++i) {
-            PriorityQueue q = fullQueue(N);
-            PriorityQueue p = fullQueue(i);
+    /**
+     * removeAll(c) removes only those elements of c and reports true if changed
+     */
+    public void testRemoveAll() {
+        for (int i = 1; i < SIZE; ++i) {
+            PriorityQueue q = populatedQueue(SIZE);
+            PriorityQueue p = populatedQueue(i);
             assertTrue(q.removeAll(p));
-            assertEquals(N-i, q.size());
+            assertEquals(SIZE - i, q.size());
             for (int j = 0; j < i; ++j) {
-                Integer I = (Integer)(p.remove());
-                assertFalse(q.contains(I));
+                Integer x = (Integer)(p.remove());
+                assertFalse(q.contains(x));
             }
         }
     }
 
-    public void testToArray(){
-        PriorityQueue q = fullQueue(N);
-	Object[] o = q.toArray();
-        Arrays.sort(o);
-	for(int i = 0; i < o.length; i++)
-	    assertEquals(o[i], q.poll());
+    /**
+     * toArray contains all elements
+     */
+    public void testToArray() {
+        PriorityQueue q = populatedQueue(SIZE);
+        Object[] a = q.toArray();
+        assertSame(Object[].class, a.getClass());
+        Arrays.sort(a);
+        for (Object o : a)
+            assertSame(o, q.poll());
+        assertTrue(q.isEmpty());
     }
 
-    public void testToArray2(){
-        PriorityQueue q = fullQueue(N);
-	Integer[] ints = new Integer[N];
-	ints = (Integer[])q.toArray(ints);
+    /**
+     * toArray(a) contains all elements
+     */
+    public void testToArray2() {
+        PriorityQueue<Integer> q = populatedQueue(SIZE);
+        Integer[] ints = new Integer[SIZE];
+        Integer[] array = q.toArray(ints);
+        assertSame(ints, array);
         Arrays.sort(ints);
-        for(int i = 0; i < ints.length; i++)
-            assertEquals(ints[i], q.poll());
+        for (Integer o : ints)
+            assertSame(o, q.poll());
+        assertTrue(q.isEmpty());
     }
-    
-    public void testIterator(){
-        PriorityQueue q = fullQueue(N);
-        int i = 0;
-	Iterator it = q.iterator();
-        while(it.hasNext()) {
+
+    /**
+     * iterator iterates through all elements
+     */
+    public void testIterator() {
+        PriorityQueue q = populatedQueue(SIZE);
+        Iterator it = q.iterator();
+        int i;
+        for (i = 0; it.hasNext(); i++)
             assertTrue(q.contains(it.next()));
-            ++i;
-        }
-        assertEquals(i, N);
+        assertEquals(i, SIZE);
+        assertIteratorExhausted(it);
     }
 
-    public void testIteratorRemove () {
+    /**
+     * iterator of empty collection has no elements
+     */
+    public void testEmptyIterator() {
+        assertIteratorExhausted(new PriorityQueue().iterator());
+    }
 
+    /**
+     * iterator.remove removes current element
+     */
+    public void testIteratorRemove() {
         final PriorityQueue q = new PriorityQueue(3);
-
         q.add(new Integer(2));
         q.add(new Integer(1));
         q.add(new Integer(3));
@@ -380,31 +497,30 @@ public class PriorityQueueTest extends T
         assertFalse(it.hasNext());
     }
 
-
-    public void testToString(){
-        PriorityQueue q = fullQueue(N);
+    /**
+     * toString contains toStrings of elements
+     */
+    public void testToString() {
+        PriorityQueue q = populatedQueue(SIZE);
         String s = q.toString();
-        for (int i = 0; i < N; ++i) {
-            assertTrue(s.indexOf(String.valueOf(i)) >= 0);
+        for (int i = 0; i < SIZE; ++i) {
+            assertTrue(s.contains(String.valueOf(i)));
         }
-    }        
+    }
 
-    public void testSerialization() {
-        PriorityQueue q = fullQueue(N);
-        try {
-            ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
-            ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
-            out.writeObject(q);
-            out.close();
-
-            ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
-            ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
-            PriorityQueue r = (PriorityQueue)in.readObject();
-            assertEquals(q.size(), r.size());
-            while (!q.isEmpty()) 
-                assertEquals(q.remove(), r.remove());
-        } catch(Exception e){
-            fail("unexpected exception");
+    /**
+     * A deserialized/reserialized queue has same elements
+     */
+    public void testSerialization() throws Exception {
+        Queue x = populatedQueue(SIZE);
+        Queue y = serialClone(x);
+
+        assertNotSame(x, y);
+        assertEquals(x.size(), y.size());
+        while (!x.isEmpty()) {
+            assertFalse(y.isEmpty());
+            assertEquals(x.remove(), y.remove());
         }
+        assertTrue(y.isEmpty());
     }
 }