/*

 * Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.

 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 6362121

 * @summary Test one ScheduledThreadPoolExecutor extension scenario

 * @author Martin Buchholz

 */

// based on a test kindly provided by Holger Hoffstaette <holger@wizards.de>

import java.util.concurrent.*;

import static java.util.concurrent.TimeUnit.MILLISECONDS;

public class ScheduledTickleService {

    // We get intermittent ClassCastException if greater than 1

    // because of calls to compareTo

    // Record when tasks are done

    public static void realMain(String... args) throws InterruptedException {

        // our tickle service

        ScheduledExecutorService tickleService =

            new ScheduledThreadPoolExecutor(concurrency) {

                // We override decorateTask() to return a custom

                // RunnableScheduledFuture which explicitly removes

                // itself from the queue after cancellation.

                protected <V> RunnableScheduledFuture<V>

                    decorateTask(Runnable runnable,

                                 RunnableScheduledFuture<V> task) {

                    final ScheduledThreadPoolExecutor exec = this;

                    return new CustomRunnableScheduledFuture<V>(task) {

                        // delegate to wrapped task, except for:

                        public boolean cancel(boolean b) {

                            // cancel wrapped task & remove myself from the queue

                            return (task().cancel(b)

                                    && exec.remove(this));}};}};

        for (int i = 0; i < concurrency; i++)

            new ScheduledTickle(i, tickleService)

                .setUpdateInterval(25, MILLISECONDS);

        done.await();

        tickleService.shutdown();

        pass();

    }

    // our Runnable

    static class ScheduledTickle implements Runnable {

        public volatile int failures = 0;

        // my tickle service

        private final ScheduledExecutorService service;

        // remember my own scheduled ticket

        private ScheduledFuture ticket = null;

        // remember the number of times I've been tickled

        private int numTickled = 0;

        // my private name

        private final String name;

        public ScheduledTickle(int i, ScheduledExecutorService service) {

            super();

            this.name = "Tickler-"+i;

            this.service = service;

        }

        // set my tickle interval; 0 to disable further tickling.

        public synchronized void setUpdateInterval(long interval,

                                                   TimeUnit unit) {

            // cancel & remove previously created ticket

            if (ticket != null) {

                ticket.cancel(false);

                ticket = null;

            }

            if (interval > 0 && ! service.isShutdown()) {

                // requeue with new interval

                ticket = service.scheduleAtFixedRate(this, interval,

                                                     interval, unit);

            }

        }

        public synchronized void run() {

            try {

                check(numTickled < 6);

                numTickled++;

                System.out.println(name + ": Run " + numTickled);

                // tickle 3 times and then slow down

                if (numTickled == 3) {

                    System.out.println(name + ": slower please!");

                    this.setUpdateInterval(100, MILLISECONDS);

                }

                // ..but only 5 times max.

                else if (numTickled == 5) {

                    System.out.println(name + ": OK that's enough.");

                    this.setUpdateInterval(0, MILLISECONDS);

                    ScheduledTickleService.done.countDown();

                }

            } catch (Throwable t) { unexpected(t); }

        }

    }

    // This is just a generic wrapper to make up for the private ScheduledFutureTask

    static class CustomRunnableScheduledFuture<V>

        implements RunnableScheduledFuture<V> {

        // the wrapped future

        private RunnableScheduledFuture<V> task;

        public CustomRunnableScheduledFuture(RunnableScheduledFuture<V> task) {

            super();

            this.task = task;

        }

        public RunnableScheduledFuture<V> task() { return task; }

        // Forwarding methods

        public boolean isPeriodic()         { return task.isPeriodic(); }

        public boolean isCancelled()        { return task.isCancelled(); }

        public boolean isDone()             { return task.isDone(); }

        public boolean cancel(boolean b)    { return task.cancel(b); }

        public long getDelay(TimeUnit unit) { return task.getDelay(unit); }

        public void run()                   {        task.run(); }

        public V get()

            throws InterruptedException, ExecutionException {

            return task.get();

        }

        public V get(long timeout, TimeUnit unit)

            throws InterruptedException, ExecutionException, TimeoutException {

            return task.get(timeout, unit);

        }

        public int compareTo(Delayed other) {

            if (this == other)

                return 0;

            else if (other instanceof CustomRunnableScheduledFuture)

                return task.compareTo(((CustomRunnableScheduledFuture)other).task());

            else

                return task.compareTo(other);

        }

    }

    //--------------------- Infrastructure ---------------------------

    static volatile int passed = 0, failed = 0;

    static void pass() {passed++;}

    static void fail() {failed++; Thread.dumpStack();}

    static void fail(String msg) {System.out.println(msg); fail();}

    static void unexpected(Throwable t) {failed++; t.printStackTrace();}

    static void check(boolean cond) {if (cond) pass(); else fail();}

    static void equal(Object x, Object y) {

        if (x == null ? y == null : x.equals(y)) pass();

        else fail(x + " not equal to " + y);}

    public static void main(String[] args) throws Throwable {

        try {realMain(args);} catch (Throwable t) {unexpected(t);}

        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

        if (failed > 0) throw new AssertionError("Some tests failed");}

}