/*
 * Copyright (c) 2005, 2011, 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 6233235 6268386
 * @summary Test allowsCoreThreadTimeOut
 * @library /test/lib
 * @author Martin Buchholz
 */

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

import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import jdk.test.lib.Utils;

public class CoreThreadTimeOut {
    static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);

    static class IdentifiableThreadFactory implements ThreadFactory {
        static ThreadFactory defaultThreadFactory
            = Executors.defaultThreadFactory();

        public Thread newThread(Runnable r) {
            Thread t = defaultThreadFactory.newThread(r);
            t.setName("CoreThreadTimeOut-" + t.getName());
            return t;
        }
    }

    int countExecutorThreads() {
        Thread[] threads = new Thread[Thread.activeCount()+100];
        Thread.enumerate(threads);
        int count = 0;
        for (Thread t : threads)
            if (t != null &&
                t.getName().matches
                ("CoreThreadTimeOut-pool-[0-9]+-thread-[0-9]+"))
                count++;
        return count;
    }

    static long millisElapsedSince(long startTime) {
        return (System.nanoTime() - startTime) / (1000L * 1000L);
    }

    void test(String[] args) throws Throwable {
        final int threadCount = 10;
        final int timeoutMillis = 30;
        BlockingQueue<Runnable> q = new ArrayBlockingQueue<>(2*threadCount);
        ThreadPoolExecutor tpe
            = new ThreadPoolExecutor(threadCount, threadCount,
                                     timeoutMillis, TimeUnit.MILLISECONDS,
                                     q, new IdentifiableThreadFactory());
        equal(tpe.getCorePoolSize(), threadCount);
        check(! tpe.allowsCoreThreadTimeOut());
        tpe.allowCoreThreadTimeOut(true);
        check(tpe.allowsCoreThreadTimeOut());
        equal(countExecutorThreads(), 0);
        long startTime = System.nanoTime();
        for (int i = 0; i < threadCount; i++) {
            tpe.submit(() -> {});
            int count = countExecutorThreads();
            if (millisElapsedSince(startTime) < timeoutMillis)
                equal(count, i + 1);
        }
        while (countExecutorThreads() > 0 &&
               millisElapsedSince(startTime) < LONG_DELAY_MS)
            Thread.yield();
        equal(countExecutorThreads(), 0);
        check(millisElapsedSince(startTime) >= timeoutMillis);
        tpe.shutdown();
        check(tpe.allowsCoreThreadTimeOut());
        check(tpe.awaitTermination(LONG_DELAY_MS, MILLISECONDS));

        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
        if (failed > 0) throw new Exception("Some tests failed");
    }

    //--------------------- Infrastructure ---------------------------
    volatile int passed = 0, failed = 0;
    void pass() {passed++;}
    void fail() {failed++; Thread.dumpStack();}
    void fail(String msg) {System.err.println(msg); fail();}
    void unexpected(Throwable t) {failed++; t.printStackTrace();}
    void check(boolean cond) {if (cond) pass(); else fail();}
    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 {
        new CoreThreadTimeOut().instanceMain(args);}
    public void instanceMain(String[] args) throws Throwable {
        try {test(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");}
}