Added jsr166 tck tests as part of the libcore testsuite.

Change-Id: I6094d734f818fa043f2b277cf2b4ec7fec68e26e
diff --git a/jsr166-tests/src/test/java/jsr166/JSR166TestCase.java b/jsr166-tests/src/test/java/jsr166/JSR166TestCase.java
new file mode 100644
index 0000000..d9bf255
--- /dev/null
+++ b/jsr166-tests/src/test/java/jsr166/JSR166TestCase.java
@@ -0,0 +1,1140 @@
+/*
+ * 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.
+ */
+
+package jsr166;
+
+import junit.framework.*;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.lang.reflect.Method;
+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.*;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicReference;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.concurrent.TimeUnit.NANOSECONDS;
+import java.security.CodeSource;
+import java.security.Permission;
+import java.security.PermissionCollection;
+import java.security.Permissions;
+import java.security.Policy;
+import java.security.ProtectionDomain;
+import java.security.SecurityPermission;
+
+/**
+ * Base class for JSR166 Junit TCK tests.  Defines some constants,
+ * utility methods and classes, as well as a simple framework for
+ * helping to make sure that assertions failing in generated threads
+ * cause the associated test that generated them to itself fail (which
+ * JUnit does not otherwise arrange).  The rules for creating such
+ * tests are:
+ *
+ * <ol>
+ *
+ * <li> All assertions in code running in generated threads must use
+ * the forms {@link #threadFail}, {@link #threadAssertTrue}, {@link
+ * #threadAssertEquals}, or {@link #threadAssertNull}, (not
+ * {@code fail}, {@code assertTrue}, etc.) It is OK (but not
+ * particularly recommended) for other code to use these forms too.
+ * Only the most typically used JUnit assertion methods are defined
+ * this way, but enough to live with.</li>
+ *
+ * <li> If you override {@link #setUp} or {@link #tearDown}, make sure
+ * to invoke {@code super.setUp} and {@code super.tearDown} within
+ * them. These methods are used to clear and check for thread
+ * assertion failures.</li>
+ *
+ * <li>All delays and timeouts must use one of the constants {@code
+ * SHORT_DELAY_MS}, {@code SMALL_DELAY_MS}, {@code MEDIUM_DELAY_MS},
+ * {@code LONG_DELAY_MS}. The idea here is that a SHORT is always
+ * discriminable from zero time, and always allows enough time for the
+ * small amounts of computation (creating a thread, calling a few
+ * methods, etc) needed to reach a timeout point. Similarly, a SMALL
+ * is always discriminable as larger than SHORT and smaller than
+ * MEDIUM.  And so on. These constants are set to conservative values,
+ * but even so, if there is ever any doubt, they can all be increased
+ * in one spot to rerun tests on slower platforms.</li>
+ *
+ * <li> All threads generated must be joined inside each test case
+ * method (or {@code fail} to do so) before returning from the
+ * method. The {@code joinPool} method can be used to do this when
+ * using Executors.</li>
+ *
+ * </ol>
+ *
+ * <p><b>Other notes</b>
+ * <ul>
+ *
+ * <li> Usually, there is one testcase method per JSR166 method
+ * covering "normal" operation, and then as many exception-testing
+ * methods as there are exceptions the method can throw. Sometimes
+ * there are multiple tests per JSR166 method when the different
+ * "normal" behaviors differ significantly. And sometimes testcases
+ * cover multiple methods when they cannot be tested in
+ * isolation.</li>
+ *
+ * <li> The documentation style for testcases is to provide as javadoc
+ * a simple sentence or two describing the property that the testcase
+ * method purports to test. The javadocs do not say anything about how
+ * the property is tested. To find out, read the code.</li>
+ *
+ * <li> These tests are "conformance tests", and do not attempt to
+ * test throughput, latency, scalability or other performance factors
+ * (see the separate "jtreg" tests for a set intended to check these
+ * for the most central aspects of functionality.) So, most tests use
+ * the smallest sensible numbers of threads, collection sizes, etc
+ * needed to check basic conformance.</li>
+ *
+ * <li>The test classes currently do not declare inclusion in
+ * any particular package to simplify things for people integrating
+ * them in TCK test suites.</li>
+ *
+ * <li> As a convenience, the {@code main} of this class (JSR166TestCase)
+ * runs all JSR166 unit tests.</li>
+ *
+ * </ul>
+ */
+public class JSR166TestCase extends TestCase {
+
+    protected static final boolean expensiveTests = false;
+
+    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.
+     */
+    protected long getShortDelay() {
+        return 50;
+    }
+
+    /**
+     * Sets delays as multiples of SHORT_DELAY.
+     */
+    protected void setDelays() {
+        SHORT_DELAY_MS = getShortDelay();
+        SMALL_DELAY_MS  = SHORT_DELAY_MS * 5;
+        MEDIUM_DELAY_MS = SHORT_DELAY_MS * 10;
+        LONG_DELAY_MS   = SHORT_DELAY_MS * 200;
+    }
+
+    /**
+     * 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
+        = new AtomicReference<Throwable>(null);
+
+    /**
+     * Records an exception so that it can be rethrown later in the test
+     * harness thread, triggering a test case failure.  Only the first
+     * failure is recorded; subsequent calls to this method from within
+     * the same test have no effect.
+     */
+    public void threadRecordFailure(Throwable t) {
+        threadFailure.compareAndSet(null, t);
+    }
+
+    public void setUp() {
+        setDelays();
+    }
+
+    /**
+     * 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);
+        if (t != null) {
+            if (t instanceof Error)
+                throw (Error) t;
+            else if (t instanceof RuntimeException)
+                throw (RuntimeException) t;
+            else if (t instanceof Exception)
+                throw (Exception) t;
+            else {
+                AssertionFailedError afe =
+                    new AssertionFailedError(t.toString());
+                afe.initCause(t);
+                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));
+            }
+        }
+    }
+
+    /**
+     * Just like fail(reason), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadFail(String reason) {
+        try {
+            fail(reason);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            fail(reason);
+        }
+    }
+
+    /**
+     * Just like assertTrue(b), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertTrue(boolean b) {
+        try {
+            assertTrue(b);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        }
+    }
+
+    /**
+     * Just like assertFalse(b), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertFalse(boolean b) {
+        try {
+            assertFalse(b);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        }
+    }
+
+    /**
+     * Just like assertNull(x), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertNull(Object x) {
+        try {
+            assertNull(x);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        }
+    }
+
+    /**
+     * Just like assertEquals(x, y), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertEquals(long x, long y) {
+        try {
+            assertEquals(x, y);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        }
+    }
+
+    /**
+     * Just like assertEquals(x, y), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertEquals(Object x, Object y) {
+        try {
+            assertEquals(x, y);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        } catch (Throwable t) {
+            threadUnexpectedException(t);
+        }
+    }
+
+    /**
+     * Just like assertSame(x, y), but additionally recording (using
+     * threadRecordFailure) any AssertionFailedError thrown, so that
+     * the current testcase will fail.
+     */
+    public void threadAssertSame(Object x, Object y) {
+        try {
+            assertSame(x, y);
+        } catch (AssertionFailedError t) {
+            threadRecordFailure(t);
+            throw t;
+        }
+    }
+
+    /**
+     * Calls threadFail with message "should throw exception".
+     */
+    public void threadShouldThrow() {
+        threadFail("should throw exception");
+    }
+
+    /**
+     * Calls threadFail with message "should throw" + exceptionName.
+     */
+    public void threadShouldThrow(String exceptionName) {
+        threadFail("should throw " + exceptionName);
+    }
+
+    /**
+     * Records the given exception using {@link #threadRecordFailure},
+     * then rethrows the exception, wrapping it in an
+     * AssertionFailedError if necessary.
+     */
+    public void threadUnexpectedException(Throwable t) {
+        threadRecordFailure(t);
+        t.printStackTrace();
+        if (t instanceof RuntimeException)
+            throw (RuntimeException) t;
+        else if (t instanceof Error)
+            throw (Error) t;
+        else {
+            AssertionFailedError afe =
+                new AssertionFailedError("unexpected exception: " + t);
+            afe.initCause(t);
+            throw afe;
+        }
+    }
+
+    /**
+     * 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.
+     */
+    static void delay(long millis) throws InterruptedException {
+        long startTime = System.nanoTime();
+        long ns = millis * 1000 * 1000;
+        for (;;) {
+            if (millis > 0L)
+                Thread.sleep(millis);
+            else // too short to sleep
+                Thread.yield();
+            long d = ns - (System.nanoTime() - startTime);
+            if (d > 0L)
+                millis = d / (1000 * 1000);
+            else
+                break;
+        }
+    }
+
+    /**
+     * Waits out termination of a thread pool or fails doing so.
+     */
+    void joinPool(ExecutorService exec) {
+        try {
+            exec.shutdown();
+            assertTrue("ExecutorService did not terminate in a timely manner",
+                       exec.awaitTermination(2 * LONG_DELAY_MS, MILLISECONDS));
+        } catch (SecurityException ok) {
+            // Allowed in case test doesn't have privs
+        } catch (InterruptedException ie) {
+            fail("Unexpected InterruptedException");
+        }
+    }
+
+    /**
+     * 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".
+     */
+    public void shouldThrow() {
+        fail("Should throw exception");
+    }
+
+    /**
+     * Fails with message "should throw " + exceptionName.
+     */
+    public void shouldThrow(String exceptionName) {
+        fail("Should throw " + exceptionName);
+    }
+
+    /**
+     * The number of elements to place in collections, arrays, etc.
+     */
+    public static final int SIZE = 20;
+
+    // Some convenient Integer constants
+
+    public static final Integer zero  = new Integer(0);
+    public static final Integer one   = new Integer(1);
+    public static final Integer two   = new Integer(2);
+    public static final Integer three = new Integer(3);
+    public static final Integer four  = new Integer(4);
+    public static final Integer five  = new Integer(5);
+    public static final Integer six   = new Integer(6);
+    public static final Integer seven = new Integer(7);
+    public static final Integer eight = new Integer(8);
+    public static final Integer nine  = new Integer(9);
+    public static final Integer m1  = new Integer(-1);
+    public static final Integer m2  = new Integer(-2);
+    public static final Integer m3  = new Integer(-3);
+    public static final Integer m4  = new Integer(-4);
+    public static final Integer m5  = new Integer(-5);
+    public static final Integer m6  = new Integer(-6);
+    public static final Integer m10 = new Integer(-10);
+
+
+    /**
+     * android-changed
+     * Android does not use a SecurityManager. This will simply execute
+     * the runnable ingoring permisions.
+     */
+    public void runWithPermissions(Runnable r, Permission... permissions) {
+        r.run();
+    }
+
+    /**
+     * android-changed
+     * Android does not use a SecurityManager. This will simply execute
+     * the runnable ingoring permisions.
+     */
+    public void runWithSecurityManagerWithPermissions(Runnable r,
+                                                      Permission... permissions) {
+        r.run();
+    }
+
+    /**
+     * Runs a runnable without any permissions.
+     */
+    public void runWithoutPermissions(Runnable r) {
+        runWithPermissions(r);
+    }
+
+    /**
+     * A security policy where new permissions can be dynamically added
+     * or all cleared.
+     */
+    public static class AdjustablePolicy extends java.security.Policy {
+        Permissions perms = new Permissions();
+        AdjustablePolicy(Permission... permissions) {
+            for (Permission permission : permissions)
+                perms.add(permission);
+        }
+        void addPermission(Permission perm) { perms.add(perm); }
+        void clearPermissions() { perms = new Permissions(); }
+        public PermissionCollection getPermissions(CodeSource cs) {
+            return perms;
+        }
+        public PermissionCollection getPermissions(ProtectionDomain pd) {
+            return perms;
+        }
+        public boolean implies(ProtectionDomain pd, Permission p) {
+            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;
+        }
+    }
+
+    /**
+     * Returns a policy containing all the permissions we ever need.
+     */
+    public static Policy permissivePolicy() {
+        return new AdjustablePolicy
+            // Permissions j.u.c. needs directly
+            (new RuntimePermission("modifyThread"),
+             new RuntimePermission("getClassLoader"),
+             new RuntimePermission("setContextClassLoader"),
+             // Permissions needed to change permissions!
+             new SecurityPermission("getPolicy"),
+             new SecurityPermission("setPolicy"),
+             new RuntimePermission("setSecurityManager"),
+             // Permissions needed by the junit test harness
+             new RuntimePermission("accessDeclaredMembers"),
+             new PropertyPermission("*", "read"),
+             new java.io.FilePermission("<<ALL FILES>>", "read"));
+    }
+
+    /**
+     * Sleeps until the given time has elapsed.
+     * Throws AssertionFailedError if interrupted.
+     */
+    void sleep(long millis) {
+        try {
+            delay(millis);
+        } catch (InterruptedException ie) {
+            AssertionFailedError afe =
+                new AssertionFailedError("Unexpected InterruptedException");
+            afe.initCause(ie);
+            throw afe;
+        }
+    }
+
+    /**
+     * 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 startTime = System.nanoTime();
+        for (;;) {
+            Thread.State s = thread.getState();
+            if (s == Thread.State.BLOCKED ||
+                s == Thread.State.WAITING ||
+                s == Thread.State.TIMED_WAITING)
+                return;
+            else if (s == Thread.State.TERMINATED)
+                fail("Unexpected thread termination");
+            else if (millisElapsedSince(startTime) > timeoutMillis) {
+                threadAssertTrue(thread.isAlive());
+                return;
+            }
+            Thread.yield();
+        }
+    }
+
+    /**
+     * Waits up to LONG_DELAY_MS for the given thread to enter a wait
+     * state: BLOCKED, WAITING, or TIMED_WAITING.
+     */
+    void waitForThreadToEnterWaitState(Thread thread) {
+        waitForThreadToEnterWaitState(thread, LONG_DELAY_MS);
+    }
+
+    /**
+     * Returns the number of milliseconds since time given by
+     * startNanoTime, which must have been previously returned from a
+     * call to {@link System.nanoTime()}.
+     */
+    long millisElapsedSince(long startNanoTime) {
+        return NANOSECONDS.toMillis(System.nanoTime() - startNanoTime);
+    }
+
+    /**
+     * Returns a new started daemon Thread running the given runnable.
+     */
+    Thread newStartedThread(Runnable runnable) {
+        Thread t = new Thread(runnable);
+        t.setDaemon(true);
+        t.start();
+        return t;
+    }
+
+    /**
+     * Waits for the specified time (in milliseconds) for the thread
+     * to terminate (using {@link Thread#join(long)}), else interrupts
+     * the thread (in the hope that it may terminate later) and fails.
+     */
+    void awaitTermination(Thread t, long timeoutMillis) {
+        try {
+            t.join(timeoutMillis);
+        } catch (InterruptedException ie) {
+            threadUnexpectedException(ie);
+        } finally {
+            if (t.getState() != Thread.State.TERMINATED) {
+                t.interrupt();
+                fail("Test timed out");
+            }
+        }
+    }
+
+    /**
+     * Waits for LONG_DELAY_MS milliseconds for the thread to
+     * terminate (using {@link Thread#join(long)}), else interrupts
+     * the thread (in the hope that it may terminate later) and fails.
+     */
+    void awaitTermination(Thread t) {
+        awaitTermination(t, LONG_DELAY_MS);
+    }
+
+    // Some convenient Runnable classes
+
+    public abstract class CheckedRunnable implements Runnable {
+        protected abstract void realRun() throws Throwable;
+
+        public final void run() {
+            try {
+                realRun();
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+            }
+        }
+    }
+
+    public abstract class RunnableShouldThrow implements Runnable {
+        protected abstract void realRun() throws Throwable;
+
+        final Class<?> exceptionClass;
+
+        <T extends Throwable> RunnableShouldThrow(Class<T> exceptionClass) {
+            this.exceptionClass = exceptionClass;
+        }
+
+        public final void run() {
+            try {
+                realRun();
+                threadShouldThrow(exceptionClass.getSimpleName());
+            } catch (Throwable t) {
+                if (! exceptionClass.isInstance(t))
+                    threadUnexpectedException(t);
+            }
+        }
+    }
+
+    public abstract class ThreadShouldThrow extends Thread {
+        protected abstract void realRun() throws Throwable;
+
+        final Class<?> exceptionClass;
+
+        <T extends Throwable> ThreadShouldThrow(Class<T> exceptionClass) {
+            this.exceptionClass = exceptionClass;
+        }
+
+        public final void run() {
+            try {
+                realRun();
+                threadShouldThrow(exceptionClass.getSimpleName());
+            } catch (Throwable t) {
+                if (! exceptionClass.isInstance(t))
+                    threadUnexpectedException(t);
+            }
+        }
+    }
+
+    public abstract class CheckedInterruptedRunnable implements Runnable {
+        protected abstract void realRun() throws Throwable;
+
+        public final void run() {
+            try {
+                realRun();
+                threadShouldThrow("InterruptedException");
+            } catch (InterruptedException success) {
+                threadAssertFalse(Thread.interrupted());
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+            }
+        }
+    }
+
+    public abstract class CheckedCallable<T> implements Callable<T> {
+        protected abstract T realCall() throws Throwable;
+
+        public final T call() {
+            try {
+                return realCall();
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+                return null;
+            }
+        }
+    }
+
+    public abstract class CheckedInterruptedCallable<T>
+        implements Callable<T> {
+        protected abstract T realCall() throws Throwable;
+
+        public final T call() {
+            try {
+                T result = realCall();
+                threadShouldThrow("InterruptedException");
+                return result;
+            } catch (InterruptedException success) {
+                threadAssertFalse(Thread.interrupted());
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+            }
+            return null;
+        }
+    }
+
+    public static class NoOpRunnable implements Runnable {
+        public void run() {}
+    }
+
+    public static class NoOpCallable implements Callable {
+        public Object call() { return Boolean.TRUE; }
+    }
+
+    public static final String TEST_STRING = "a test string";
+
+    public static class StringTask implements Callable<String> {
+        public String call() { return TEST_STRING; }
+    }
+
+    public Callable<String> latchAwaitingStringTask(final CountDownLatch latch) {
+        return new CheckedCallable<String>() {
+            protected String realCall() {
+                try {
+                    latch.await();
+                } catch (InterruptedException quittingTime) {}
+                return TEST_STRING;
+            }};
+    }
+
+    public Runnable awaiter(final CountDownLatch latch) {
+        return new CheckedRunnable() {
+            public void realRun() throws InterruptedException {
+                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(); }
+    }
+
+    public static class CallableOne implements Callable<Integer> {
+        public Integer call() { return one; }
+    }
+
+    public class ShortRunnable extends CheckedRunnable {
+        protected void realRun() throws Throwable {
+            delay(SHORT_DELAY_MS);
+        }
+    }
+
+    public class ShortInterruptedRunnable extends CheckedInterruptedRunnable {
+        protected void realRun() throws InterruptedException {
+            delay(SHORT_DELAY_MS);
+        }
+    }
+
+    public class SmallRunnable extends CheckedRunnable {
+        protected void realRun() throws Throwable {
+            delay(SMALL_DELAY_MS);
+        }
+    }
+
+    public class SmallPossiblyInterruptedRunnable extends CheckedRunnable {
+        protected void realRun() {
+            try {
+                delay(SMALL_DELAY_MS);
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public class SmallCallable extends CheckedCallable {
+        protected Object realCall() throws InterruptedException {
+            delay(SMALL_DELAY_MS);
+            return Boolean.TRUE;
+        }
+    }
+
+    public class MediumRunnable extends CheckedRunnable {
+        protected void realRun() throws Throwable {
+            delay(MEDIUM_DELAY_MS);
+        }
+    }
+
+    public class MediumInterruptedRunnable extends CheckedInterruptedRunnable {
+        protected void realRun() throws InterruptedException {
+            delay(MEDIUM_DELAY_MS);
+        }
+    }
+
+    public Runnable possiblyInterruptedRunnable(final long timeoutMillis) {
+        return new CheckedRunnable() {
+            protected void realRun() {
+                try {
+                    delay(timeoutMillis);
+                } catch (InterruptedException ok) {}
+            }};
+    }
+
+    public class MediumPossiblyInterruptedRunnable extends CheckedRunnable {
+        protected void realRun() {
+            try {
+                delay(MEDIUM_DELAY_MS);
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public class LongPossiblyInterruptedRunnable extends CheckedRunnable {
+        protected void realRun() {
+            try {
+                delay(LONG_DELAY_MS);
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    /**
+     * For use as ThreadFactory in constructors
+     */
+    public static class SimpleThreadFactory implements ThreadFactory {
+        public Thread newThread(Runnable r) {
+            return new Thread(r);
+        }
+    }
+
+    public interface TrackedRunnable extends Runnable {
+        boolean isDone();
+    }
+
+    public static TrackedRunnable trackedRunnable(final long timeoutMillis) {
+        return new TrackedRunnable() {
+                private volatile boolean done = false;
+                public boolean isDone() { return done; }
+                public void run() {
+                    try {
+                        delay(timeoutMillis);
+                        done = true;
+                    } catch (InterruptedException ok) {}
+                }
+            };
+    }
+
+    public static class TrackedShortRunnable implements Runnable {
+        public volatile boolean done = false;
+        public void run() {
+            try {
+                delay(SHORT_DELAY_MS);
+                done = true;
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public static class TrackedSmallRunnable implements Runnable {
+        public volatile boolean done = false;
+        public void run() {
+            try {
+                delay(SMALL_DELAY_MS);
+                done = true;
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public static class TrackedMediumRunnable implements Runnable {
+        public volatile boolean done = false;
+        public void run() {
+            try {
+                delay(MEDIUM_DELAY_MS);
+                done = true;
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public static class TrackedLongRunnable implements Runnable {
+        public volatile boolean done = false;
+        public void run() {
+            try {
+                delay(LONG_DELAY_MS);
+                done = true;
+            } catch (InterruptedException ok) {}
+        }
+    }
+
+    public static class TrackedNoOpRunnable implements Runnable {
+        public volatile boolean done = false;
+        public void run() {
+            done = true;
+        }
+    }
+
+    public static class TrackedCallable implements Callable {
+        public volatile boolean done = false;
+        public Object call() {
+            try {
+                delay(SMALL_DELAY_MS);
+                done = true;
+            } catch (InterruptedException ok) {}
+            return Boolean.TRUE;
+        }
+    }
+
+    /**
+     * Analog of CheckedRunnable for RecursiveAction
+     */
+    public abstract class CheckedRecursiveAction extends RecursiveAction {
+        protected abstract void realCompute() throws Throwable;
+
+        @Override protected final void compute() {
+            try {
+                realCompute();
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+            }
+        }
+    }
+
+    /**
+     * Analog of CheckedCallable for RecursiveTask
+     */
+    public abstract class CheckedRecursiveTask<T> extends RecursiveTask<T> {
+        protected abstract T realCompute() throws Throwable;
+
+        @Override protected final T compute() {
+            try {
+                return realCompute();
+            } catch (Throwable t) {
+                threadUnexpectedException(t);
+                return null;
+            }
+        }
+    }
+
+    /**
+     * For use as RejectedExecutionHandler in constructors
+     */
+    public static class NoOpREHandler implements RejectedExecutionHandler {
+        public void rejectedExecution(Runnable r,
+                                      ThreadPoolExecutor executor) {}
+    }
+
+    /**
+     * 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(2 * LONG_DELAY_MS, MILLISECONDS);
+            } catch (TimeoutException e) {
+                throw new AssertionFailedError("timed out");
+            } catch (Exception e) {
+                AssertionFailedError afe =
+                    new AssertionFailedError("Unexpected exception: " + e);
+                afe.initCause(e);
+                throw afe;
+            }
+        }
+    }
+
+    void checkEmpty(BlockingQueue q) {
+        try {
+            assertTrue(q.isEmpty());
+            assertEquals(0, q.size());
+            assertNull(q.peek());
+            assertNull(q.poll());
+            assertNull(q.poll(0, MILLISECONDS));
+            assertEquals(q.toString(), "[]");
+            assertTrue(Arrays.equals(q.toArray(), new Object[0]));
+            assertFalse(q.iterator().hasNext());
+            try {
+                q.element();
+                shouldThrow();
+            } catch (NoSuchElementException success) {}
+            try {
+                q.iterator().next();
+                shouldThrow();
+            } catch (NoSuchElementException success) {}
+            try {
+                q.remove();
+                shouldThrow();
+            } catch (NoSuchElementException success) {}
+        } catch (InterruptedException ie) {
+            threadUnexpectedException(ie);
+        }
+    }
+
+    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());
+        }
+    }
+}