/*
 * Copyright (c) 2017, 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.
 */


import java.lang.management.*;
import com.sun.management.OperatingSystemMXBean;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

import javax.management.Notification;
import javax.management.NotificationEmitter;
import javax.management.NotificationListener;

public class ServiceThread {
    public static void main(String[] args) throws InterruptedException {

        ((NotificationEmitter) ManagementFactory.getMemoryMXBean()).addNotificationListener(new NotificationListener() {

            @Override
            public void handleNotification(Notification pNotification, Object pHandback) {
                System.out.println("notification...");
            }
        }, null, null);

        for (MemoryPoolMXBean m : ManagementFactory.getMemoryPoolMXBeans()) {
            if (m.getType() == MemoryType.HEAP) {
                MemoryUsage localMemoryUsage = m.getUsage();
                long l = (long) (localMemoryUsage.getMax() == -1L ? 
                         Runtime.getRuntime().maxMemory() * 0.9D : localMemoryUsage.getMax() * 0.9D);
                m.setCollectionUsageThreshold(l);
            }
        }

        ExecutorService pool = Executors.newFixedThreadPool(5);
        List<Future<?>> futures = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            futures.add(pool.submit(new Runnable() {
                @Override
                public void run() {
                    try {
                        Random random = new Random();
                        List<String> interned = new ArrayList<>();
                        while (true) {
                            int length = random.nextInt(100);
                            StringBuilder builder = new StringBuilder();
                            String sample = "whoisyourdaddy";
                            for (int i = 0; i < length; i++) {
                                builder.append(sample.charAt(random.nextInt(sample.length())));
                            }
                            interned.add(builder.toString().intern());
                        }

                    } catch (Throwable t) {
                        System.out.println(Thread.currentThread().getName() + ": " + t);
                        throw t;
                    }
                }
            }));
        }
        
        int m = 0;
        while (m < 2) {
            Thread.sleep(60000);
            m++;
            final Iterator<Future<?>> iter = futures.iterator();
            while (iter.hasNext()) {
                Future<?> future = iter.next();
                System.out.println("\tfuture task DONE: " + future.isDone());
                if (future.isDone()) {
                    iter.remove();
                }
            }
            if (futures.isEmpty()) {
                if (!pool.isShutdown()) {
                    System.out.println("\tshutting down thread pool...");
                    pool.shutdown();
                } 
            }
        }

        OperatingSystemMXBean os = (com.sun.management.OperatingSystemMXBean)ManagementFactory.getOperatingSystemMXBean();
        double load = os.getProcessCpuLoad()*100;
        System.out.println("Process CPU Load: "+ load);
        if (load > 5){
            System.out.println("Test Failed...");
            System.exit(1);
        } else {
            System.out.println("Test Passed...");
            System.exit(0);
        }
    }
}