--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/util/concurrent/FutureTask/CancelledFutureLoops.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,145 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file:
+ *
+ * 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/licenses/publicdomain
+ */
+
+/*
+ * @test
+ * @bug 4486658
+ * @compile -source 1.5 CancelledFutureLoops.java
+ * @run main/timeout=2000 CancelledFutureLoops
+ * @summary Checks for responsiveness of futures to cancellation.
+ * Runs under the assumption that ITERS computations require more than
+ * TIMEOUT msecs to complete.
+ */
+
+import java.util.concurrent.*;
+import java.util.concurrent.locks.*;
+import java.util.*;
+
+public final class CancelledFutureLoops {
+    static final ExecutorService pool = Executors.newCachedThreadPool();
+    static final LoopHelpers.SimpleRandom rng = new LoopHelpers.SimpleRandom();
+    static boolean print = false;
+    static final int ITERS = 1000000;
+    static final long TIMEOUT = 100;
+
+    public static void main(String[] args) throws Exception {
+        int maxThreads = 5;
+        if (args.length > 0)
+            maxThreads = Integer.parseInt(args[0]);
+
+        print = true;
+
+        for (int i = 2; i <= maxThreads; i += (i+1) >>> 1) {
+            System.out.print("Threads: " + i);
+            try {
+                new FutureLoop(i).test();
+            }
+            catch(BrokenBarrierException bb) {
+                // OK; ignore
+            }
+            catch(ExecutionException ee) {
+                // OK; ignore
+            }
+            Thread.sleep(TIMEOUT);
+        }
+        pool.shutdown();
+        if (! pool.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS))
+            throw new Error();
+    }
+
+    static final class FutureLoop implements Callable {
+        private int v = rng.next();
+        private final ReentrantLock lock = new ReentrantLock();
+        private final LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
+        private final CyclicBarrier barrier;
+        private final int nthreads;
+        FutureLoop(int nthreads) {
+            this.nthreads = nthreads;
+            barrier = new CyclicBarrier(nthreads+1, timer);
+        }
+
+        final void test() throws Exception {
+            Future[] futures = new Future[nthreads];
+            for (int i = 0; i < nthreads; ++i)
+                futures[i] = pool.submit(this);
+
+            barrier.await();
+            Thread.sleep(TIMEOUT);
+            boolean tooLate = false;
+            for (int i = 1; i < nthreads; ++i) {
+                if (!futures[i].cancel(true))
+                    tooLate = true;
+                // Unbunch some of the cancels
+                if ( (i & 3) == 0)
+                    Thread.sleep(1 + rng.next() % 10);
+            }
+
+            Object f0 = futures[0].get();
+            if (!tooLate) {
+                for (int i = 1; i < nthreads; ++i) {
+                    if (!futures[i].isDone() || !futures[i].isCancelled())
+                        throw new Error("Only one thread should complete");
+                }
+            }
+            else
+                System.out.print("(cancelled too late) ");
+
+            long endTime = System.nanoTime();
+            long time = endTime - timer.startTime;
+            if (print) {
+                double secs = (double)(time) / 1000000000.0;
+                System.out.println("\t " + secs + "s run time");
+            }
+
+        }
+
+        public final Object call() throws Exception {
+            barrier.await();
+            int sum = v;
+            int x = 0;
+            int n = ITERS;
+            while (n-- > 0) {
+                lock.lockInterruptibly();
+                try {
+                    v = x = LoopHelpers.compute1(v);
+                }
+                finally {
+                    lock.unlock();
+                }
+                sum += LoopHelpers.compute2(LoopHelpers.compute2(x));
+            }
+            return new Integer(sum);
+        }
+    }
+
+}