--- jsr166/src/test/tck/PriorityBlockingQueueTest.java	2003/09/14 20:42:40	1.3
+++ jsr166/src/test/tck/PriorityBlockingQueueTest.java	2014/12/31 19:05:43	1.54
@@ -1,134 +1,178 @@
 /*
- * 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.*;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.Queue;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.PriorityBlockingQueue;
+
+import junit.framework.Test;
 
 public class PriorityBlockingQueueTest extends JSR166TestCase {
+
+    public static class Generic extends BlockingQueueTest {
+        protected BlockingQueue emptyCollection() {
+            return new PriorityBlockingQueue();
+        }
+    }
+
+    public static class InitialCapacity extends BlockingQueueTest {
+        protected BlockingQueue emptyCollection() {
+            return new PriorityBlockingQueue(SIZE);
+        }
+    }
+
     public static void main(String[] args) {
-	junit.textui.TestRunner.run (suite());	
+        junit.textui.TestRunner.run(suite());
     }
 
     public static Test suite() {
-	return new TestSuite(PriorityBlockingQueueTest.class);
+        return newTestSuite(PriorityBlockingQueueTest.class,
+                            new Generic().testSuite(),
+                            new InitialCapacity().testSuite());
     }
 
     private static final int NOCAP = Integer.MAX_VALUE;
 
     /** Sample Comparator */
-    static class MyReverseComparator implements Comparator { 
+    static class MyReverseComparator implements Comparator {
         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
+     * Returns a new queue of given size containing consecutive
      * Integers 0 ... n.
      */
-    private PriorityBlockingQueue populatedQueue(int n) {
-        PriorityBlockingQueue q = new PriorityBlockingQueue(n);
+    private PriorityBlockingQueue<Integer> populatedQueue(int n) {
+        PriorityBlockingQueue<Integer> q =
+            new PriorityBlockingQueue<Integer>(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(NOCAP, q.remainingCapacity());
-	assertEquals(n, q.size());
+        assertEquals(n, q.size());
         return q;
     }
- 
-    public void testConstructor1(){
+
+    /**
+     * A new queue has unbounded capacity
+     */
+    public void testConstructor1() {
         assertEquals(NOCAP, new PriorityBlockingQueue(SIZE).remainingCapacity());
     }
 
-    public void testConstructor2(){
+    /**
+     * Constructor throws IAE if capacity argument nonpositive
+     */
+    public void testConstructor2() {
         try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(0);
-            fail("Cannot make zero-sized");
-        }
-        catch (IllegalArgumentException success) {}
+            new PriorityBlockingQueue(0);
+            shouldThrow();
+        } catch (IllegalArgumentException success) {}
     }
 
-    public void testConstructor3(){
-
+    /**
+     * Initializing from null Collection throws NPE
+     */
+    public void testConstructor3() {
         try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(null);
-            fail("Cannot make from null collection");
-        }
-        catch (NullPointerException success) {}
+            new PriorityBlockingQueue(null);
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor4(){
+    /**
+     * Initializing from Collection of null elements throws NPE
+     */
+    public void testConstructor4() {
+        Collection<Integer> elements = Arrays.asList(new Integer[SIZE]);
         try {
-            Integer[] ints = new Integer[SIZE];
-            PriorityBlockingQueue q = new PriorityBlockingQueue(Arrays.asList(ints));
-            fail("Cannot make with null elements");
-        }
-        catch (NullPointerException success) {}
+            new PriorityBlockingQueue(elements);
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor5(){
-        try {
-            Integer[] ints = new Integer[SIZE];
-            for (int i = 0; i < SIZE-1; ++i)
-                ints[i] = new Integer(i);
-            PriorityBlockingQueue q = new PriorityBlockingQueue(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] = i;
+        Collection<Integer> elements = Arrays.asList(ints);
+        try {
+            new PriorityBlockingQueue(elements);
+            shouldThrow();
+        } catch (NullPointerException success) {}
     }
 
-    public void testConstructor6(){
-        try {
-            Integer[] ints = new Integer[SIZE];
-            for (int i = 0; i < SIZE; ++i)
-                ints[i] = new Integer(i);
-            PriorityBlockingQueue q = new PriorityBlockingQueue(Arrays.asList(ints));
-            for (int i = 0; i < SIZE; ++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] = i;
+        PriorityBlockingQueue q = new PriorityBlockingQueue(Arrays.asList(ints));
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(ints[i], q.poll());
     }
 
-    public void testConstructor7(){
-        try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE, new MyReverseComparator());
-            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());
-        }
-        finally {}
+    /**
+     * The comparator used in constructor is used
+     */
+    public void testConstructor7() {
+        MyReverseComparator cmp = new MyReverseComparator();
+        PriorityBlockingQueue q = new PriorityBlockingQueue(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() {
         PriorityBlockingQueue q = new PriorityBlockingQueue(2);
         assertTrue(q.isEmpty());
         assertEquals(NOCAP, q.remainingCapacity());
-        q.add(new Integer(1));
+        q.add(one);
         assertFalse(q.isEmpty());
-        q.add(new Integer(2));
+        q.add(two);
         q.remove();
         q.remove();
         assertTrue(q.isEmpty());
     }
 
-    public void testRemainingCapacity(){
+    /**
+     * remainingCapacity does not change when elements added or removed,
+     * but size does
+     */
+    public void testRemainingCapacity() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
             assertEquals(NOCAP, q.remainingCapacity());
@@ -142,32 +186,32 @@ public class PriorityBlockingQueueTest e
         }
     }
 
-    public void testOfferNull(){
-	try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(1);
-            q.offer(null);
-            fail("should throw NPE");
-        } catch (NullPointerException success) { }   
-    }
-
+    /**
+     * Offer of comparable element succeeds
+     */
     public void testOffer() {
         PriorityBlockingQueue q = new PriorityBlockingQueue(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() {
         try {
             PriorityBlockingQueue q = new PriorityBlockingQueue(1);
             q.offer(new Object());
             q.offer(new Object());
             q.offer(new Object());
-            fail("should throw CCE");
-        }
-        catch(ClassCastException success) {}
+            shouldThrow();
+        } catch (ClassCastException success) {}
     }
 
-    public void testAdd(){
+    /**
+     * add of comparable succeeds
+     */
+    public void testAdd() {
         PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
             assertEquals(i, q.size());
@@ -175,311 +219,251 @@ public class PriorityBlockingQueueTest e
         }
     }
 
-    public void testAddAll1(){
-        try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(1);
-            q.addAll(null);
-            fail("Cannot add null collection");
-        }
-        catch (NullPointerException success) {}
-    }
-    public void testAddAll2(){
+    /**
+     * addAll(this) throws IAE
+     */
+    public void testAddAllSelf() {
         try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
-            Integer[] ints = new Integer[SIZE];
-            q.addAll(Arrays.asList(ints));
-            fail("Cannot add null elements");
-        }
-        catch (NullPointerException success) {}
+            PriorityBlockingQueue q = populatedQueue(SIZE);
+            q.addAll(q);
+            shouldThrow();
+        } catch (IllegalArgumentException success) {}
     }
-    public void testAddAll3(){
+
+    /**
+     * addAll of a collection with any null elements throws NPE after
+     * possibly adding some elements
+     */
+    public void testAddAll3() {
         try {
             PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
             Integer[] ints = new Integer[SIZE];
             for (int i = 0; i < SIZE-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[SIZE];
-            for (int i = SIZE-1; i >= 0; --i)
-                ints[i] = new Integer(i);
-            PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
-            assertFalse(q.addAll(Arrays.asList(empty)));
-            assertTrue(q.addAll(Arrays.asList(ints)));
-            for (int i = 0; i < SIZE; ++i)
-                assertEquals(ints[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 = SIZE-1; i >= 0; --i)
+            ints[i] = new Integer(i);
+        PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
+        assertFalse(q.addAll(Arrays.asList(empty)));
+        assertTrue(q.addAll(Arrays.asList(ints)));
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(ints[i], q.poll());
     }
 
-     public void testPutNull() {
-	try {
-            PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
-            q.put(null);
-            fail("put should throw NPE");
-        } 
-        catch (NullPointerException success){
-	}   
-     }
-
-     public void testPut() {
-         try {
-             PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
-             for (int i = 0; i < SIZE; ++i) {
-                 Integer I = new Integer(i);
-                 q.put(I);
-                 assertTrue(q.contains(I));
-             }
-             assertEquals(SIZE, q.size());
-         }
-         finally {
+    /**
+     * all elements successfully put are contained
+     */
+    public void testPut() {
+        PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            Integer I = new Integer(i);
+            q.put(I);
+            assertTrue(q.contains(I));
         }
+        assertEquals(SIZE, q.size());
     }
 
-    public void testPutWithTake() {
+    /**
+     * put doesn't block waiting for take
+     */
+    public void testPutWithTake() throws InterruptedException {
         final PriorityBlockingQueue q = new PriorityBlockingQueue(2);
-        Thread t = new Thread(new Runnable() {
-                public void run(){
-                    int added = 0;
-                    try {
-                        q.put(new Integer(0));
-                        ++added;
-                        q.put(new Integer(0));
-                        ++added;
-                        q.put(new Integer(0));
-                        ++added;
-                        q.put(new Integer(0));
-                        ++added;
-                        threadAssertTrue(added == 4);
-                    } finally {
-                    }
-                }
-            });
-        try {
-            t.start();
-            Thread.sleep(SHORT_DELAY_MS);
-            q.take();
-            t.interrupt();
-            t.join();
-        } catch (Exception e){
-            fail("Unexpected exception");
-        }
+        final int size = 4;
+        Thread t = newStartedThread(new CheckedRunnable() {
+            public void realRun() {
+                for (int i = 0; i < size; i++)
+                    q.put(new Integer(0));
+            }});
+
+        awaitTermination(t);
+        assertEquals(size, q.size());
+        q.take();
     }
 
-    public void testTimedOffer() {
+    /**
+     * timed offer does not time out
+     */
+    public void testTimedOffer() throws InterruptedException {
         final PriorityBlockingQueue q = new PriorityBlockingQueue(2);
-        Thread t = new Thread(new Runnable() {
-                public void run(){
-                    try {
-                        q.put(new Integer(0));
-                        q.put(new Integer(0));
-                        threadAssertTrue(q.offer(new Integer(0), SHORT_DELAY_MS, TimeUnit.MILLISECONDS));
-                        threadAssertTrue(q.offer(new Integer(0), LONG_DELAY_MS, TimeUnit.MILLISECONDS));
-                    } finally { }
-                }
-            });
-        
-        try {
-            t.start();
-            Thread.sleep(SMALL_DELAY_MS);
-            t.interrupt();
-            t.join();
-        } catch (Exception e){
-            fail("Unexpected exception");
-        }
-    }
+        Thread t = newStartedThread(new CheckedRunnable() {
+            public void realRun() {
+                q.put(new Integer(0));
+                q.put(new Integer(0));
+                assertTrue(q.offer(new Integer(0), SHORT_DELAY_MS, MILLISECONDS));
+                assertTrue(q.offer(new Integer(0), LONG_DELAY_MS, MILLISECONDS));
+            }});
 
-    public void testTake(){
-	try {
-            PriorityBlockingQueue q = populatedQueue(SIZE);
-            for (int i = 0; i < SIZE; ++i) {
-                assertEquals(i, ((Integer)q.take()).intValue());
-            }
-        } catch (InterruptedException e){
-	    fail("Unexpected exception");
-	}   
+        awaitTermination(t);
     }
 
-    public void testTakeFromEmpty() {
-        final PriorityBlockingQueue q = new PriorityBlockingQueue(2);
-        Thread t = new Thread(new Runnable() {
-                public void run(){
-                    try {
-                        q.take();
-			threadFail("Should block");
-                    } catch (InterruptedException success){ }                
-                }
-            });
-        try {
-            t.start();
-            Thread.sleep(SHORT_DELAY_MS);
-            t.interrupt();
-            t.join();
-        } catch (Exception e){
-            fail("Unexpected exception");
+    /**
+     * take retrieves elements in priority order
+     */
+    public void testTake() throws InterruptedException {
+        PriorityBlockingQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.take());
         }
     }
 
-    public void testBlockingTake(){
-        Thread t = new Thread(new Runnable() {
-                public void run() {
-                    try {
-                        PriorityBlockingQueue q = populatedQueue(SIZE);
-                        for (int i = 0; i < SIZE; ++i) {
-                            threadAssertEquals(i, ((Integer)q.take()).intValue());
-                        }
-                        q.take();
-                        threadFail("take should block");
-                    } catch (InterruptedException success){
-                    }   
-                }});
-        t.start();
-        try { 
-           Thread.sleep(SHORT_DELAY_MS); 
-           t.interrupt();
-           t.join();
-        }
-        catch (InterruptedException ie) {
-	    fail("Unexpected exception");
-        }
-    }
+    /**
+     * Take removes existing elements until empty, then blocks interruptibly
+     */
+    public void testBlockingTake() throws InterruptedException {
+        final PriorityBlockingQueue q = populatedQueue(SIZE);
+        final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
+        Thread t = newStartedThread(new CheckedRunnable() {
+            public void realRun() throws InterruptedException {
+                for (int i = 0; i < SIZE; ++i) {
+                    assertEquals(i, q.take());
+                }
 
+                Thread.currentThread().interrupt();
+                try {
+                    q.take();
+                    shouldThrow();
+                } catch (InterruptedException success) {}
+                assertFalse(Thread.interrupted());
 
-    public void testPoll(){
+                pleaseInterrupt.countDown();
+                try {
+                    q.take();
+                    shouldThrow();
+                } catch (InterruptedException success) {}
+                assertFalse(Thread.interrupted());
+            }});
+
+        await(pleaseInterrupt);
+        assertThreadStaysAlive(t);
+        t.interrupt();
+        awaitTermination(t);
+    }
+
+    /**
+     * poll succeeds unless empty
+     */
+    public void testPoll() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
-            assertEquals(i, ((Integer)q.poll()).intValue());
+            assertEquals(i, q.poll());
         }
-	assertNull(q.poll());
+        assertNull(q.poll());
     }
 
-    public void testTimedPoll0() {
-        try {
-            PriorityBlockingQueue q = populatedQueue(SIZE);
-            for (int i = 0; i < SIZE; ++i) {
-                assertEquals(i, ((Integer)q.poll(0, TimeUnit.MILLISECONDS)).intValue());
-            }
-            assertNull(q.poll(0, TimeUnit.MILLISECONDS));
-        } catch (InterruptedException e){
-	    fail("Unexpected exception");
-	}   
+    /**
+     * timed poll with zero timeout succeeds when non-empty, else times out
+     */
+    public void testTimedPoll0() throws InterruptedException {
+        PriorityBlockingQueue q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            assertEquals(i, q.poll(0, MILLISECONDS));
+        }
+        assertNull(q.poll(0, MILLISECONDS));
     }
 
-    public void testTimedPoll() {
-        try {
-            PriorityBlockingQueue q = populatedQueue(SIZE);
-            for (int i = 0; i < SIZE; ++i) {
-                assertEquals(i, ((Integer)q.poll(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)).intValue());
-            }
-            assertNull(q.poll(SHORT_DELAY_MS, TimeUnit.MILLISECONDS));
-        } catch (InterruptedException e){
-	    fail("Unexpected exception");
-	}   
-    }
-
-    public void testInterruptedTimedPoll(){
-        Thread t = new Thread(new Runnable() {
-                public void run() {
-                    try {
-                        PriorityBlockingQueue q = populatedQueue(SIZE);
-                        for (int i = 0; i < SIZE; ++i) {
-                            threadAssertEquals(i, ((Integer)q.poll(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)).intValue());
-                        }
-                        threadAssertNull(q.poll(SHORT_DELAY_MS, TimeUnit.MILLISECONDS));
-                    } catch (InterruptedException success){
-                    }   
-                }});
-        t.start();
-        try { 
-           Thread.sleep(SHORT_DELAY_MS); 
-           t.interrupt();
-           t.join();
-        }
-        catch (InterruptedException ie) {
-	    fail("Unexpected exception");
-        }
+    /**
+     * timed poll with nonzero timeout succeeds when non-empty, else times out
+     */
+    public void testTimedPoll() throws InterruptedException {
+        PriorityBlockingQueue<Integer> q = populatedQueue(SIZE);
+        for (int i = 0; i < SIZE; ++i) {
+            long startTime = System.nanoTime();
+            assertEquals(i, (int) q.poll(LONG_DELAY_MS, MILLISECONDS));
+            assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
+        }
+        long startTime = System.nanoTime();
+        assertNull(q.poll(timeoutMillis(), MILLISECONDS));
+        assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
+        checkEmpty(q);
     }
 
-    public void testTimedPollWithOffer(){
-        final PriorityBlockingQueue q = new PriorityBlockingQueue(2);
-        Thread t = new Thread(new Runnable() {
-                public void run(){
-                    try {
-                        threadAssertNull(q.poll(SHORT_DELAY_MS, TimeUnit.MILLISECONDS));
-                        q.poll(LONG_DELAY_MS, TimeUnit.MILLISECONDS);
-                        q.poll(LONG_DELAY_MS, TimeUnit.MILLISECONDS);
-			threadFail("Should block");
-                    } catch (InterruptedException success) { }                
+    /**
+     * Interrupted timed poll throws InterruptedException instead of
+     * returning timeout status
+     */
+    public void testInterruptedTimedPoll() throws InterruptedException {
+        final BlockingQueue<Integer> q = populatedQueue(SIZE);
+        final CountDownLatch aboutToWait = new CountDownLatch(1);
+        Thread t = newStartedThread(new CheckedRunnable() {
+            public void realRun() throws InterruptedException {
+                for (int i = 0; i < SIZE; ++i) {
+                    long t0 = System.nanoTime();
+                    assertEquals(i, (int) q.poll(LONG_DELAY_MS, MILLISECONDS));
+                    assertTrue(millisElapsedSince(t0) < SMALL_DELAY_MS);
                 }
-            });
-        try {
-            t.start();
-            Thread.sleep(SMALL_DELAY_MS);
-            assertTrue(q.offer(new Integer(0), SHORT_DELAY_MS, TimeUnit.MILLISECONDS));
-            t.interrupt();
-            t.join();
-        } catch (Exception e){
-            fail("Unexpected exception");
-        }
-    }  
+                long t0 = System.nanoTime();
+                aboutToWait.countDown();
+                try {
+                    q.poll(LONG_DELAY_MS, MILLISECONDS);
+                    shouldThrow();
+                } catch (InterruptedException success) {
+                    assertTrue(millisElapsedSince(t0) < MEDIUM_DELAY_MS);
+                }
+            }});
 
+        aboutToWait.await();
+        waitForThreadToEnterWaitState(t, SMALL_DELAY_MS);
+        t.interrupt();
+        awaitTermination(t, MEDIUM_DELAY_MS);
+    }
 
-    public void testPeek(){
+    /**
+     * peek returns next element, or null if empty
+     */
+    public void testPeek() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
-            assertEquals(i, ((Integer)q.peek()).intValue());
-            q.poll();
+            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(){
+    /**
+     * element returns next element, or throws NSEE if empty
+     */
+    public void testElement() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
-            assertEquals(i, ((Integer)q.element()).intValue());
-            q.poll();
+            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(){
+    /**
+     * remove removes next element, or throws NSEE if empty
+     */
+    public void testRemove() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
-            assertEquals(i, ((Integer)q.remove()).intValue());
+            assertEquals(i, q.remove());
         }
         try {
             q.remove();
-            fail("remove should throw");
-        } catch (NoSuchElementException success){
-	}   
+            shouldThrow();
+        } catch (NoSuchElementException success) {}
     }
 
-    public void testRemoveElement(){
-        PriorityBlockingQueue q = populatedQueue(SIZE);
-        for (int i = 1; i < SIZE; i+=2) {
-            assertTrue(q.remove(new Integer(i)));
-        }
-        for (int i = 0; i < SIZE; i+=2) {
-            assertTrue(q.remove(new Integer(i)));
-            assertFalse(q.remove(new Integer(i+1)));
-        }
-        assertTrue(q.isEmpty());
-    }
-	
-    public void testContains(){
+    /**
+     * contains(x) reports true when elements added but not yet removed
+     */
+    public void testContains() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
             assertTrue(q.contains(new Integer(i)));
@@ -488,19 +472,25 @@ public class PriorityBlockingQueueTest e
         }
     }
 
-    public void testClear(){
+    /**
+     * clear removes all elements
+     */
+    public void testClear() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         q.clear();
         assertTrue(q.isEmpty());
         assertEquals(0, q.size());
-        assertEquals(NOCAP, q.remainingCapacity());
-        q.add(new Integer(1));
+        q.add(one);
         assertFalse(q.isEmpty());
+        assertTrue(q.contains(one));
         q.clear();
         assertTrue(q.isEmpty());
     }
 
-    public void testContainsAll(){
+    /**
+     * containsAll(c) is true when c contains a subset of elements
+     */
+    public void testContainsAll() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         PriorityBlockingQueue p = new PriorityBlockingQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
@@ -511,7 +501,10 @@ public class PriorityBlockingQueueTest e
         assertTrue(p.containsAll(q));
     }
 
-    public void testRetainAll(){
+    /**
+     * retainAll(c) retains only those elements of c and reports true if changed
+     */
+    public void testRetainAll() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         PriorityBlockingQueue p = populatedQueue(SIZE);
         for (int i = 0; i < SIZE; ++i) {
@@ -527,7 +520,10 @@ public class PriorityBlockingQueueTest e
         }
     }
 
-    public void testRemoveAll(){
+    /**
+     * removeAll(c) removes only those elements of c and reports true if changed
+     */
+    public void testRemoveAll() {
         for (int i = 1; i < SIZE; ++i) {
             PriorityBlockingQueue q = populatedQueue(SIZE);
             PriorityBlockingQueue p = populatedQueue(i);
@@ -540,46 +536,60 @@ public class PriorityBlockingQueueTest e
         }
     }
 
-    public void testToArray(){
+    /**
+     * toArray contains all elements
+     */
+    public void testToArray() throws InterruptedException {
         PriorityBlockingQueue q = populatedQueue(SIZE);
-	Object[] o = q.toArray();
+        Object[] o = q.toArray();
         Arrays.sort(o);
-	try {
-	for(int i = 0; i < o.length; i++)
-	    assertEquals(o[i], q.take());
-	} catch (InterruptedException e){
-	    fail("Unexpected exception");
-	}    
+        for (int i = 0; i < o.length; i++)
+            assertSame(o[i], q.take());
     }
 
-    public void testToArray2(){
-        PriorityBlockingQueue q = populatedQueue(SIZE);
-	Integer[] ints = new Integer[SIZE];
-	ints = (Integer[])q.toArray(ints);
+    /**
+     * toArray(a) contains all elements
+     */
+    public void testToArray2() throws InterruptedException {
+        PriorityBlockingQueue<Integer> q = populatedQueue(SIZE);
+        Integer[] ints = new Integer[SIZE];
+        Integer[] array = q.toArray(ints);
+        assertSame(ints, array);
         Arrays.sort(ints);
-	try {
-	    for(int i = 0; i < ints.length; i++)
-		assertEquals(ints[i], q.take());
-	} catch (InterruptedException e){
-	    fail("Unexpected exception");
-	}    
+        for (int i = 0; i < ints.length; i++)
+            assertSame(ints[i], q.take());
     }
-    
-    public void testIterator(){
+
+    /**
+     * toArray(incompatible array type) throws ArrayStoreException
+     */
+    public void testToArray1_BadArg() {
+        PriorityBlockingQueue q = populatedQueue(SIZE);
+        try {
+            q.toArray(new String[10]);
+            shouldThrow();
+        } catch (ArrayStoreException success) {}
+    }
+
+    /**
+     * iterator iterates through all elements
+     */
+    public void testIterator() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         int i = 0;
-	Iterator it = q.iterator();
-        while(it.hasNext()) {
+        Iterator it = q.iterator();
+        while (it.hasNext()) {
             assertTrue(q.contains(it.next()));
             ++i;
         }
         assertEquals(i, SIZE);
     }
 
-    public void testIteratorRemove () {
-
+    /**
+     * iterator.remove removes current element
+     */
+    public void testIteratorRemove() {
         final PriorityBlockingQueue q = new PriorityBlockingQueue(3);
-
         q.add(new Integer(2));
         q.add(new Integer(1));
         q.add(new Integer(3));
@@ -594,66 +604,132 @@ public class PriorityBlockingQueueTest e
         assertFalse(it.hasNext());
     }
 
-
-    public void testToString(){
+    /**
+     * toString contains toStrings of elements
+     */
+    public void testToString() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
         String s = q.toString();
         for (int i = 0; i < SIZE; ++i) {
-            assertTrue(s.indexOf(String.valueOf(i)) >= 0);
+            assertTrue(s.contains(String.valueOf(i)));
         }
-    }        
+    }
 
+    /**
+     * timed poll transfers elements across Executor tasks
+     */
     public void testPollInExecutor() {
-
         final PriorityBlockingQueue q = new PriorityBlockingQueue(2);
-
+        final CheckedBarrier threadsStarted = new CheckedBarrier(2);
         ExecutorService executor = Executors.newFixedThreadPool(2);
+        executor.execute(new CheckedRunnable() {
+            public void realRun() throws InterruptedException {
+                assertNull(q.poll());
+                threadsStarted.await();
+                assertSame(one, q.poll(LONG_DELAY_MS, MILLISECONDS));
+                checkEmpty(q);
+            }});
+
+        executor.execute(new CheckedRunnable() {
+            public void realRun() throws InterruptedException {
+                threadsStarted.await();
+                q.put(one);
+            }});
 
-        executor.execute(new Runnable() {
-            public void run() {
-                threadAssertNull(q.poll());
-                try {
-                    threadAssertTrue(null != q.poll(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS));
-                    threadAssertTrue(q.isEmpty());
-                }
-                catch (InterruptedException e) {
-                    threadFail("should not be interrupted");
-                }
-            }
-        });
-
-        executor.execute(new Runnable() {
-            public void run() {
-                try {
-                    Thread.sleep(SMALL_DELAY_MS);
-                    q.put(new Integer(1));
-                }
-                catch (InterruptedException e) {
-                    threadFail("should not be interrupted");
-                }
-            }
-        });
-        
         joinPool(executor);
+    }
 
+    /**
+     * A deserialized serialized 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());
     }
 
-    public void testSerialization() {
+    /**
+     * drainTo(c) empties queue into another collection c
+     */
+    public void testDrainTo() {
         PriorityBlockingQueue q = populatedQueue(SIZE);
-        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));
-            PriorityBlockingQueue r = (PriorityBlockingQueue)in.readObject();
-            assertEquals(q.size(), r.size());
-            while (!q.isEmpty()) 
-                assertEquals(q.remove(), r.remove());
-        } catch(Exception e){
-            fail("unexpected exception");
+        ArrayList l = new ArrayList();
+        q.drainTo(l);
+        assertEquals(0, q.size());
+        assertEquals(SIZE, l.size());
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(l.get(i), new Integer(i));
+        q.add(zero);
+        q.add(one);
+        assertFalse(q.isEmpty());
+        assertTrue(q.contains(zero));
+        assertTrue(q.contains(one));
+        l.clear();
+        q.drainTo(l);
+        assertEquals(0, q.size());
+        assertEquals(2, l.size());
+        for (int i = 0; i < 2; ++i)
+            assertEquals(l.get(i), new Integer(i));
+    }
+
+    /**
+     * drainTo empties queue
+     */
+    public void testDrainToWithActivePut() throws InterruptedException {
+        final PriorityBlockingQueue q = populatedQueue(SIZE);
+        Thread t = new Thread(new CheckedRunnable() {
+            public void realRun() {
+                q.put(new Integer(SIZE+1));
+            }});
+
+        t.start();
+        ArrayList l = new ArrayList();
+        q.drainTo(l);
+        assertTrue(l.size() >= SIZE);
+        for (int i = 0; i < SIZE; ++i)
+            assertEquals(l.get(i), new Integer(i));
+        t.join();
+        assertTrue(q.size() + l.size() >= SIZE);
+    }
+
+    /**
+     * drainTo(c, n) empties first min(n, size) elements of queue into c
+     */
+    public void testDrainToN() {
+        PriorityBlockingQueue q = new PriorityBlockingQueue(SIZE*2);
+        for (int i = 0; i < SIZE + 2; ++i) {
+            for (int j = 0; j < SIZE; j++)
+                assertTrue(q.offer(new Integer(j)));
+            ArrayList l = new ArrayList();
+            q.drainTo(l, i);
+            int k = (i < SIZE) ? i : SIZE;
+            assertEquals(k, l.size());
+            assertEquals(SIZE-k, q.size());
+            for (int j = 0; j < k; ++j)
+                assertEquals(l.get(j), new Integer(j));
+            while (q.poll() != null) ;
+        }
+    }
+
+    /**
+     * remove(null), contains(null) always return false
+     */
+    public void testNeverContainsNull() {
+        Collection<?>[] qs = {
+            new PriorityBlockingQueue<Object>(),
+            populatedQueue(2),
+        };
+
+        for (Collection<?> q : qs) {
+            assertFalse(q.contains(null));
+            assertFalse(q.remove(null));
         }
     }