--- jsr166/src/test/tck/JSR166TestCase.java	2011/05/06 11:22:07	1.76
+++ jsr166/src/test/tck/JSR166TestCase.java	2014/12/31 19:05:42	1.123
@@ -6,14 +6,16 @@
  * Pat Fisher, Mike Judd.
  */
 
-import junit.framework.*;
-import java.util.Arrays;
-import java.util.NoSuchElementException;
-import java.util.PropertyPermission;
-import java.util.concurrent.*;
-import java.util.concurrent.atomic.AtomicReference;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.concurrent.TimeUnit.NANOSECONDS;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.lang.management.ManagementFactory;
+import java.lang.management.ThreadInfo;
+import java.lang.reflect.Method;
 import java.security.CodeSource;
 import java.security.Permission;
 import java.security.PermissionCollection;
@@ -21,6 +23,33 @@ import java.security.Permissions;
 import java.security.Policy;
 import java.security.ProtectionDomain;
 import java.security.SecurityPermission;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Date;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.PropertyPermission;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+import java.util.concurrent.RecursiveAction;
+import java.util.concurrent.RecursiveTask;
+import java.util.concurrent.RejectedExecutionHandler;
+import java.util.concurrent.Semaphore;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeoutException;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.regex.Pattern;
+
+import junit.framework.AssertionFailedError;
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
 
 /**
  * Base class for JSR166 Junit TCK tests.  Defines some constants,
@@ -63,7 +92,7 @@ import java.security.SecurityPermission;
  *
  * </ol>
  *
- * <p> <b>Other notes</b>
+ * <p><b>Other notes</b>
  * <ul>
  *
  * <li> Usually, there is one testcase method per JSR166 method
@@ -103,6 +132,13 @@ public class JSR166TestCase extends Test
         Boolean.getBoolean("jsr166.expensiveTests");
 
     /**
+     * If true, also run tests that are not part of the official tck
+     * because they test unspecified implementation details.
+     */
+    protected static final boolean testImplementationDetails =
+        Boolean.getBoolean("jsr166.testImplementationDetails");
+
+    /**
      * If true, report on stdout all "slow" tests, that is, ones that
      * take more than profileThreshold milliseconds to execute.
      */
@@ -116,27 +152,53 @@ public class JSR166TestCase extends Test
     private static final long profileThreshold =
         Long.getLong("jsr166.profileThreshold", 100);
 
+    /**
+     * The number of repetitions per test (for tickling rare bugs).
+     */
+    private static final int runsPerTest =
+        Integer.getInteger("jsr166.runsPerTest", 1);
+
+    /**
+     * A filter for tests to run, matching strings of the form
+     * methodName(className), e.g. "testInvokeAll5(ForkJoinPoolTest)"
+     * Usefully combined with jsr166.runsPerTest.
+     */
+    private static final Pattern methodFilter = methodFilter();
+
+    private static Pattern methodFilter() {
+        String regex = System.getProperty("jsr166.methodFilter");
+        return (regex == null) ? null : Pattern.compile(regex);
+    }
+
     protected void runTest() throws Throwable {
-        if (profileTests)
-            runTestProfiled();
-        else
-            super.runTest();
+        if (methodFilter == null
+            || methodFilter.matcher(toString()).find()) {
+            for (int i = 0; i < runsPerTest; i++) {
+                if (profileTests)
+                    runTestProfiled();
+                else
+                    super.runTest();
+            }
+        }
     }
 
     protected void runTestProfiled() throws Throwable {
+        // Warmup run, notably to trigger all needed classloading.
+        super.runTest();
         long t0 = System.nanoTime();
         try {
             super.runTest();
         } finally {
-            long elapsedMillis =
-                (System.nanoTime() - t0) / (1000L * 1000L);
+            long elapsedMillis = millisElapsedSince(t0);
             if (elapsedMillis >= profileThreshold)
                 System.out.printf("%n%s: %d%n", toString(), elapsedMillis);
         }
     }
 
     /**
-     * Runs all JSR166 unit tests using junit.textui.TestRunner
+     * Runs all JSR166 unit tests using junit.textui.TestRunner.
+     * Optional command line arg provides the number of iterations to
+     * repeat running the tests.
      */
     public static void main(String[] args) {
         if (useSecurityManager) {
@@ -168,11 +230,51 @@ public class JSR166TestCase extends Test
         return suite;
     }
 
+    public static void addNamedTestClasses(TestSuite suite,
+                                           String... testClassNames) {
+        for (String testClassName : testClassNames) {
+            try {
+                Class<?> testClass = Class.forName(testClassName);
+                Method m = testClass.getDeclaredMethod("suite",
+                                                       new Class<?>[0]);
+                suite.addTest(newTestSuite((Test)m.invoke(null)));
+            } catch (Exception e) {
+                throw new Error("Missing test class", e);
+            }
+        }
+    }
+
+    public static final double JAVA_CLASS_VERSION;
+    public static final String JAVA_SPECIFICATION_VERSION;
+    static {
+        try {
+            JAVA_CLASS_VERSION = java.security.AccessController.doPrivileged(
+                new java.security.PrivilegedAction<Double>() {
+                public Double run() {
+                    return Double.valueOf(System.getProperty("java.class.version"));}});
+            JAVA_SPECIFICATION_VERSION = java.security.AccessController.doPrivileged(
+                new java.security.PrivilegedAction<String>() {
+                public String run() {
+                    return System.getProperty("java.specification.version");}});
+        } catch (Throwable t) {
+            throw new Error(t);
+        }
+    }
+
+    public static boolean atLeastJava6() { return JAVA_CLASS_VERSION >= 50.0; }
+    public static boolean atLeastJava7() { return JAVA_CLASS_VERSION >= 51.0; }
+    public static boolean atLeastJava8() { return JAVA_CLASS_VERSION >= 52.0; }
+    public static boolean atLeastJava9() {
+        // As of 2014-05, java9 still uses 52.0 class file version
+        return JAVA_SPECIFICATION_VERSION.startsWith("1.9");
+    }
+
     /**
      * Collects all JSR166 unit tests as one suite.
      */
     public static Test suite() {
-        return newTestSuite(
+        // Java7+ test classes
+        TestSuite suite = newTestSuite(
             ForkJoinPoolTest.suite(),
             ForkJoinTaskTest.suite(),
             RecursiveActionTest.suite(),
@@ -237,15 +339,45 @@ public class JSR166TestCase extends Test
             TreeSetTest.suite(),
             TreeSubMapTest.suite(),
             TreeSubSetTest.suite());
+
+        // Java8+ test classes
+        if (atLeastJava8()) {
+            String[] java8TestClassNames = {
+                "Atomic8Test",
+                "CompletableFutureTest",
+                "ConcurrentHashMap8Test",
+                "CountedCompleterTest",
+                "DoubleAccumulatorTest",
+                "DoubleAdderTest",
+                "ForkJoinPool8Test",
+                "ForkJoinTask8Test",
+                "LongAccumulatorTest",
+                "LongAdderTest",
+                "SplittableRandomTest",
+                "StampedLockTest",
+                "ThreadLocalRandom8Test",
+            };
+            addNamedTestClasses(suite, java8TestClassNames);
+        }
+
+        // Java9+ test classes
+        if (atLeastJava9()) {
+            String[] java9TestClassNames = {
+                "ThreadPoolExecutor9Test",
+            };
+            addNamedTestClasses(suite, java9TestClassNames);
+        }
+
+        return suite;
     }
 
+    // Delays for timing-dependent tests, in milliseconds.
 
     public static long SHORT_DELAY_MS;
     public static long SMALL_DELAY_MS;
     public static long MEDIUM_DELAY_MS;
     public static long LONG_DELAY_MS;
 
-
     /**
      * Returns the shortest timed delay. This could
      * be reimplemented to use for example a Property.
@@ -254,7 +386,6 @@ public class JSR166TestCase extends Test
         return 50;
     }
 
-
     /**
      * Sets delays as multiples of SHORT_DELAY.
      */
@@ -266,6 +397,22 @@ public class JSR166TestCase extends Test
     }
 
     /**
+     * Returns a timeout in milliseconds to be used in tests that
+     * verify that operations block or time out.
+     */
+    long timeoutMillis() {
+        return SHORT_DELAY_MS / 4;
+    }
+
+    /**
+     * Returns a new Date instance representing a time delayMillis
+     * milliseconds in the future.
+     */
+    Date delayedDate(long delayMillis) {
+        return new Date(System.currentTimeMillis() + delayMillis);
+    }
+
+    /**
      * The first exception encountered if any threadAssertXXX method fails.
      */
     private final AtomicReference<Throwable> threadFailure
@@ -286,9 +433,13 @@ public class JSR166TestCase extends Test
     }
 
     /**
+     * Extra checks that get done for all test cases.
+     *
      * Triggers test case failure if any thread assertions have failed,
      * by rethrowing, in the test harness thread, any exception recorded
      * earlier by threadRecordFailure.
+     *
+     * Triggers test case failure if interrupt status is set in the main thread.
      */
     public void tearDown() throws Exception {
         Throwable t = threadFailure.getAndSet(null);
@@ -306,6 +457,32 @@ public class JSR166TestCase extends Test
                 throw afe;
             }
         }
+
+        if (Thread.interrupted())
+            throw new AssertionFailedError("interrupt status set in main thread");
+
+        checkForkJoinPoolThreadLeaks();
+    }
+
+    /**
+     * Find missing try { ... } finally { joinPool(e); }
+     */
+    void checkForkJoinPoolThreadLeaks() throws InterruptedException {
+        Thread[] survivors = new Thread[5];
+        int count = Thread.enumerate(survivors);
+        for (int i = 0; i < count; i++) {
+            Thread thread = survivors[i];
+            String name = thread.getName();
+            if (name.startsWith("ForkJoinPool-")) {
+                // give thread some time to terminate
+                thread.join(LONG_DELAY_MS);
+                if (!thread.isAlive()) continue;
+                thread.stop();
+                throw new AssertionFailedError
+                    (String.format("Found leaked ForkJoinPool thread test=%s thread=%s%n",
+                                   toString(), name));
+            }
+        }
     }
 
     /**
@@ -437,27 +614,27 @@ public class JSR166TestCase extends Test
         else {
             AssertionFailedError afe =
                 new AssertionFailedError("unexpected exception: " + t);
-            t.initCause(t);
+            afe.initCause(t);
             throw afe;
         }
     }
 
     /**
-     * Delays, via Thread.sleep for the given millisecond delay, but
+     * Delays, via Thread.sleep, for the given millisecond delay, but
      * if the sleep is shorter than specified, may re-sleep or yield
      * until time elapses.
      */
-    public static void delay(long ms) throws InterruptedException {
+    static void delay(long millis) throws InterruptedException {
         long startTime = System.nanoTime();
-        long ns = ms * 1000 * 1000; 
+        long ns = millis * 1000 * 1000;
         for (;;) {
-            if (ms > 0L)
-                Thread.sleep(ms);
+            if (millis > 0L)
+                Thread.sleep(millis);
             else // too short to sleep
                 Thread.yield();
             long d = ns - (System.nanoTime() - startTime);
             if (d > 0L)
-                ms = d / (1000 * 1000); 
+                millis = d / (1000 * 1000);
             else
                 break;
         }
@@ -466,11 +643,12 @@ public class JSR166TestCase extends Test
     /**
      * Waits out termination of a thread pool or fails doing so.
      */
-    public void joinPool(ExecutorService exec) {
+    void joinPool(ExecutorService exec) {
         try {
             exec.shutdown();
-            assertTrue("ExecutorService did not terminate in a timely manner",
-                       exec.awaitTermination(2 * LONG_DELAY_MS, MILLISECONDS));
+            if (!exec.awaitTermination(2 * LONG_DELAY_MS, MILLISECONDS))
+                fail("ExecutorService " + exec +
+                     " did not terminate in a timely manner");
         } catch (SecurityException ok) {
             // Allowed in case test doesn't have privs
         } catch (InterruptedException ie) {
@@ -478,6 +656,81 @@ public class JSR166TestCase extends Test
         }
     }
 
+    /**
+     * A debugging tool to print all stack traces, as jstack does.
+     */
+    static void printAllStackTraces() {
+        for (ThreadInfo info :
+                 ManagementFactory.getThreadMXBean()
+                 .dumpAllThreads(true, true))
+            System.err.print(info);
+    }
+
+    /**
+     * Checks that thread does not terminate within the default
+     * millisecond delay of {@code timeoutMillis()}.
+     */
+    void assertThreadStaysAlive(Thread thread) {
+        assertThreadStaysAlive(thread, timeoutMillis());
+    }
+
+    /**
+     * Checks that thread does not terminate within the given millisecond delay.
+     */
+    void assertThreadStaysAlive(Thread thread, long millis) {
+        try {
+            // No need to optimize the failing case via Thread.join.
+            delay(millis);
+            assertTrue(thread.isAlive());
+        } catch (InterruptedException ie) {
+            fail("Unexpected InterruptedException");
+        }
+    }
+
+    /**
+     * Checks that the threads do not terminate within the default
+     * millisecond delay of {@code timeoutMillis()}.
+     */
+    void assertThreadsStayAlive(Thread... threads) {
+        assertThreadsStayAlive(timeoutMillis(), threads);
+    }
+
+    /**
+     * Checks that the threads do not terminate within the given millisecond delay.
+     */
+    void assertThreadsStayAlive(long millis, Thread... threads) {
+        try {
+            // No need to optimize the failing case via Thread.join.
+            delay(millis);
+            for (Thread thread : threads)
+                assertTrue(thread.isAlive());
+        } catch (InterruptedException ie) {
+            fail("Unexpected InterruptedException");
+        }
+    }
+
+    /**
+     * Checks that future.get times out, with the default timeout of
+     * {@code timeoutMillis()}.
+     */
+    void assertFutureTimesOut(Future future) {
+        assertFutureTimesOut(future, timeoutMillis());
+    }
+
+    /**
+     * Checks that future.get times out, with the given millisecond timeout.
+     */
+    void assertFutureTimesOut(Future future, long timeoutMillis) {
+        long startTime = System.nanoTime();
+        try {
+            future.get(timeoutMillis, MILLISECONDS);
+            shouldThrow();
+        } catch (TimeoutException success) {
+        } catch (Exception e) {
+            threadUnexpectedException(e);
+        } finally { future.cancel(true); }
+        assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
+    }
 
     /**
      * Fails with message "should throw exception".
@@ -518,7 +771,6 @@ public class JSR166TestCase extends Test
     public static final Integer m6  = new Integer(-6);
     public static final Integer m10 = new Integer(-10);
 
-
     /**
      * Runs Runnable r with a security policy that permits precisely
      * the specified permissions.  If there is no current security
@@ -530,11 +782,26 @@ public class JSR166TestCase extends Test
         SecurityManager sm = System.getSecurityManager();
         if (sm == null) {
             r.run();
+        }
+        runWithSecurityManagerWithPermissions(r, permissions);
+    }
+
+    /**
+     * Runs Runnable r with a security policy that permits precisely
+     * the specified permissions.  If there is no current security
+     * manager, a temporary one is set for the duration of the
+     * Runnable.  We require that any security manager permit
+     * getPolicy/setPolicy.
+     */
+    public void runWithSecurityManagerWithPermissions(Runnable r,
+                                                      Permission... permissions) {
+        SecurityManager sm = System.getSecurityManager();
+        if (sm == null) {
             Policy savedPolicy = Policy.getPolicy();
             try {
                 Policy.setPolicy(permissivePolicy());
                 System.setSecurityManager(new SecurityManager());
-                runWithPermissions(r, permissions);
+                runWithSecurityManagerWithPermissions(r, permissions);
             } finally {
                 System.setSecurityManager(null);
                 Policy.setPolicy(savedPolicy);
@@ -582,6 +849,12 @@ public class JSR166TestCase extends Test
             return perms.implies(p);
         }
         public void refresh() {}
+        public String toString() {
+            List<Permission> ps = new ArrayList<Permission>();
+            for (Enumeration<Permission> e = perms.elements(); e.hasMoreElements();)
+                ps.add(e.nextElement());
+            return "AdjustablePolicy with permissions " + ps;
+        }
     }
 
     /**
@@ -619,22 +892,11 @@ public class JSR166TestCase extends Test
     }
 
     /**
-     * Sleeps until the timeout has elapsed, or interrupted.
-     * Does <em>NOT</em> throw InterruptedException.
-     */
-    void sleepTillInterrupted(long timeoutMillis) {
-        try {
-            Thread.sleep(timeoutMillis);
-        } catch (InterruptedException wakeup) {}
-    }
-
-    /**
-     * Waits up to the specified number of milliseconds for the given
+     * Spin-waits up to the specified number of milliseconds for the given
      * thread to enter a wait state: BLOCKED, WAITING, or TIMED_WAITING.
      */
     void waitForThreadToEnterWaitState(Thread thread, long timeoutMillis) {
-        long timeoutNanos = timeoutMillis * 1000L * 1000L;
-        long t0 = System.nanoTime();
+        long startTime = System.nanoTime();
         for (;;) {
             Thread.State s = thread.getState();
             if (s == Thread.State.BLOCKED ||
@@ -643,7 +905,7 @@ public class JSR166TestCase extends Test
                 return;
             else if (s == Thread.State.TERMINATED)
                 fail("Unexpected thread termination");
-            else if (System.nanoTime() - t0 > timeoutNanos) {
+            else if (millisElapsedSince(startTime) > timeoutMillis) {
                 threadAssertTrue(thread.isAlive());
                 return;
             }
@@ -664,10 +926,40 @@ public class JSR166TestCase extends Test
      * startNanoTime, which must have been previously returned from a
      * call to {@link System.nanoTime()}.
      */
-    long millisElapsedSince(long startNanoTime) {
+    static long millisElapsedSince(long startNanoTime) {
         return NANOSECONDS.toMillis(System.nanoTime() - startNanoTime);
     }
 
+//     void assertTerminatesPromptly(long timeoutMillis, Runnable r) {
+//         long startTime = System.nanoTime();
+//         try {
+//             r.run();
+//         } catch (Throwable fail) { threadUnexpectedException(fail); }
+//         if (millisElapsedSince(startTime) > timeoutMillis/2)
+//             throw new AssertionFailedError("did not return promptly");
+//     }
+
+//     void assertTerminatesPromptly(Runnable r) {
+//         assertTerminatesPromptly(LONG_DELAY_MS/2, r);
+//     }
+
+    /**
+     * Checks that timed f.get() returns the expected value, and does not
+     * wait for the timeout to elapse before returning.
+     */
+    <T> void checkTimedGet(Future<T> f, T expectedValue, long timeoutMillis) {
+        long startTime = System.nanoTime();
+        try {
+            assertEquals(expectedValue, f.get(timeoutMillis, MILLISECONDS));
+        } catch (Throwable fail) { threadUnexpectedException(fail); }
+        if (millisElapsedSince(startTime) > timeoutMillis/2)
+            throw new AssertionFailedError("timed get did not return promptly");
+    }
+
+    <T> void checkTimedGet(Future<T> f, T expectedValue) {
+        checkTimedGet(f, expectedValue, LONG_DELAY_MS);
+    }
+
     /**
      * Returns a new started daemon Thread running the given runnable.
      */
@@ -689,7 +981,7 @@ public class JSR166TestCase extends Test
         } catch (InterruptedException ie) {
             threadUnexpectedException(ie);
         } finally {
-            if (t.isAlive()) {
+            if (t.getState() != Thread.State.TERMINATED) {
                 t.interrupt();
                 fail("Test timed out");
             }
@@ -767,6 +1059,7 @@ public class JSR166TestCase extends Test
                 realRun();
                 threadShouldThrow("InterruptedException");
             } catch (InterruptedException success) {
+                threadAssertFalse(Thread.interrupted());
             } catch (Throwable t) {
                 threadUnexpectedException(t);
             }
@@ -796,6 +1089,7 @@ public class JSR166TestCase extends Test
                 threadShouldThrow("InterruptedException");
                 return result;
             } catch (InterruptedException success) {
+                threadAssertFalse(Thread.interrupted());
             } catch (Throwable t) {
                 threadUnexpectedException(t);
             }
@@ -830,10 +1124,45 @@ public class JSR166TestCase extends Test
     public Runnable awaiter(final CountDownLatch latch) {
         return new CheckedRunnable() {
             public void realRun() throws InterruptedException {
-                latch.await();
+                await(latch);
             }};
     }
 
+    public void await(CountDownLatch latch) {
+        try {
+            assertTrue(latch.await(LONG_DELAY_MS, MILLISECONDS));
+        } catch (Throwable t) {
+            threadUnexpectedException(t);
+        }
+    }
+
+    public void await(Semaphore semaphore) {
+        try {
+            assertTrue(semaphore.tryAcquire(LONG_DELAY_MS, MILLISECONDS));
+        } catch (Throwable t) {
+            threadUnexpectedException(t);
+        }
+    }
+
+//     /**
+//      * Spin-waits up to LONG_DELAY_MS until flag becomes true.
+//      */
+//     public void await(AtomicBoolean flag) {
+//         await(flag, LONG_DELAY_MS);
+//     }
+
+//     /**
+//      * Spin-waits up to the specified timeout until flag becomes true.
+//      */
+//     public void await(AtomicBoolean flag, long timeoutMillis) {
+//         long startTime = System.nanoTime();
+//         while (!flag.get()) {
+//             if (millisElapsedSince(startTime) > timeoutMillis)
+//                 throw new AssertionFailedError("timed out");
+//             Thread.yield();
+//         }
+//     }
+
     public static class NPETask implements Callable<String> {
         public String call() { throw new NullPointerException(); }
     }
@@ -1002,7 +1331,7 @@ public class JSR166TestCase extends Test
     public abstract class CheckedRecursiveAction extends RecursiveAction {
         protected abstract void realCompute() throws Throwable;
 
-        public final void compute() {
+        @Override protected final void compute() {
             try {
                 realCompute();
             } catch (Throwable t) {
@@ -1017,7 +1346,7 @@ public class JSR166TestCase extends Test
     public abstract class CheckedRecursiveTask<T> extends RecursiveTask<T> {
         protected abstract T realCompute() throws Throwable;
 
-        public final T compute() {
+        @Override protected final T compute() {
             try {
                 return realCompute();
             } catch (Throwable t) {
@@ -1036,15 +1365,17 @@ public class JSR166TestCase extends Test
     }
 
     /**
-     * A CyclicBarrier that fails with AssertionFailedErrors instead
-     * of throwing checked exceptions.
+     * A CyclicBarrier that uses timed await and fails with
+     * AssertionFailedErrors instead of throwing checked exceptions.
      */
     public class CheckedBarrier extends CyclicBarrier {
         public CheckedBarrier(int parties) { super(parties); }
 
         public int await() {
             try {
-                return super.await();
+                return super.await(2 * LONG_DELAY_MS, MILLISECONDS);
+            } catch (TimeoutException e) {
+                throw new AssertionFailedError("timed out");
             } catch (Exception e) {
                 AssertionFailedError afe =
                     new AssertionFailedError("Unexpected exception: " + e);
@@ -1054,7 +1385,7 @@ public class JSR166TestCase extends Test
         }
     }
 
-    public void checkEmpty(BlockingQueue q) {
+    void checkEmpty(BlockingQueue q) {
         try {
             assertTrue(q.isEmpty());
             assertEquals(0, q.size());
@@ -1081,4 +1412,60 @@ public class JSR166TestCase extends Test
         }
     }
 
+    void assertSerialEquals(Object x, Object y) {
+        assertTrue(Arrays.equals(serialBytes(x), serialBytes(y)));
+    }
+
+    void assertNotSerialEquals(Object x, Object y) {
+        assertFalse(Arrays.equals(serialBytes(x), serialBytes(y)));
+    }
+
+    byte[] serialBytes(Object o) {
+        try {
+            ByteArrayOutputStream bos = new ByteArrayOutputStream();
+            ObjectOutputStream oos = new ObjectOutputStream(bos);
+            oos.writeObject(o);
+            oos.flush();
+            oos.close();
+            return bos.toByteArray();
+        } catch (Throwable t) {
+            threadUnexpectedException(t);
+            return new byte[0];
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    <T> T serialClone(T o) {
+        try {
+            ObjectInputStream ois = new ObjectInputStream
+                (new ByteArrayInputStream(serialBytes(o)));
+            T clone = (T) ois.readObject();
+            assertSame(o.getClass(), clone.getClass());
+            return clone;
+        } catch (Throwable t) {
+            threadUnexpectedException(t);
+            return null;
+        }
+    }
+
+    public void assertThrows(Class<? extends Throwable> expectedExceptionClass,
+                             Runnable... throwingActions) {
+        for (Runnable throwingAction : throwingActions) {
+            boolean threw = false;
+            try { throwingAction.run(); }
+            catch (Throwable t) {
+                threw = true;
+                if (!expectedExceptionClass.isInstance(t)) {
+                    AssertionFailedError afe =
+                        new AssertionFailedError
+                        ("Expected " + expectedExceptionClass.getName() +
+                         ", got " + t.getClass().getName());
+                    afe.initCause(t);
+                    threadUnexpectedException(afe);
+                }
+            }
+            if (!threw)
+                shouldThrow(expectedExceptionClass.getName());
+        }
+    }
 }