001/* 002 * #%L 003 * Netarchivesuite - common - test 004 * %% 005 * Copyright (C) 2005 - 2014 The Royal Danish Library, the Danish State and University Library, 006 * the National Library of France and the Austrian National Library. 007 * %% 008 * This program is free software: you can redistribute it and/or modify 009 * it under the terms of the GNU Lesser General Public License as 010 * published by the Free Software Foundation, either version 2.1 of the 011 * License, or (at your option) any later version. 012 * 013 * This program is distributed in the hope that it will be useful, 014 * but WITHOUT ANY WARRANTY; without even the implied warranty of 015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 016 * GNU General Lesser Public License for more details. 017 * 018 * You should have received a copy of the GNU General Lesser Public 019 * License along with this program. If not, see 020 * <http://www.gnu.org/licenses/lgpl-2.1.html>. 021 * #L% 022 */ 023 024package dk.netarkivet.testutils; 025 026import java.lang.management.ManagementFactory; 027import java.lang.management.ThreadMXBean; 028 029public abstract class ThreadUtils { 030 private static ThreadGroup rootThreadGroup = null; 031 032 public static Thread[] getAllThreads() { 033 final ThreadGroup root = getRootThreadGroup(); 034 final ThreadMXBean thbean = ManagementFactory.getThreadMXBean(); 035 int nAlloc = thbean.getThreadCount(); 036 int n = 0; 037 Thread[] threads; 038 do { 039 nAlloc *= 2; 040 threads = new Thread[nAlloc]; 041 n = root.enumerate(threads, true); 042 } while (n == nAlloc); 043 return java.util.Arrays.copyOf(threads, n); 044 } 045 046 public static ThreadGroup getRootThreadGroup() { 047 if (rootThreadGroup != null) { 048 return rootThreadGroup; 049 } 050 ThreadGroup tg = Thread.currentThread().getThreadGroup(); 051 ThreadGroup ptg; 052 while ((ptg = tg.getParent()) != null) { 053 tg = ptg; 054 } 055 return tg; 056 } 057}