Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 Lachlan Dowding
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

import java.util.Arrays;

public class Main {
    /**
     * Returns a list of all the threads in the current context.
     *
     * @return A list of all the threads in the current context.
     */
    public static Thread[] listThreads() {
        ThreadGroup root = getRootThreadGroup();

        int threadCount = 0, iteration = 0;
        Thread[] list = new Thread[threadCount];

        // because ThreadGroup.enumerate isn't thread save, keep trying to
        // enumerate for up to 10 times until we happen to have an array
        // large enough to hold all the threads that exist at the moment
        // enumerate is called
        while (iteration < 10 && threadCount >= list.length) {
            list = new Thread[root.activeCount() + (500 * ++iteration)];
            threadCount = root.enumerate(list, true);
        }

        return Arrays.copyOf(list, threadCount);
    }

    /**
     * Returns the root thread group.
     *
     * @return The root thread group.
     */
    public static ThreadGroup getRootThreadGroup() {
        ThreadGroup group = getCurrentThread().getThreadGroup();
        ThreadGroup parent = group.getParent();

        while (parent != null) {
            group = parent;
            parent = group.getParent();
        }

        return group;
    }

    /**
     * Returns the currently executing thread.
     *
     * @return The currently executing thread.
     */
    public static Thread getCurrentThread() {
        return Thread.currentThread();
    }
}