| /* |
| * Copyright (c) 2004, 2015, 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 5047639 |
| * @summary Check that the "java-level" APIs provide a consistent view of |
| * the thread list |
| */ |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.ThreadMXBean; |
| import java.util.Map; |
| |
| public class ThreadLists { |
| public static void main(String args[]) { |
| |
| // Bug id : JDK-8151797 |
| // Use a lambda expression so that call-site cleaner thread is started |
| Runnable printLambda = () -> {System.out.println("Starting Test");}; |
| printLambda.run(); |
| |
| // get top-level thread group |
| ThreadGroup top = Thread.currentThread().getThreadGroup(); |
| ThreadGroup parent; |
| do { |
| parent = top.getParent(); |
| if (parent != null) top = parent; |
| } while (parent != null); |
| |
| // get the thread count |
| int activeCount = top.activeCount(); |
| |
| Map<Thread, StackTraceElement[]> stackTraces = Thread.getAllStackTraces(); |
| |
| ThreadMXBean threadBean = ManagementFactory.getThreadMXBean(); |
| int threadCount = threadBean.getThreadCount(); |
| long[] threadIds = threadBean.getAllThreadIds(); |
| |
| System.out.println("ThreadGroup: " + activeCount + " active thread(s)"); |
| System.out.println("Thread: " + stackTraces.size() + " stack trace(s) returned"); |
| System.out.println("ThreadMXBean: " + threadCount + " live threads(s)"); |
| System.out.println("ThreadMXBean: " + threadIds.length + " thread Id(s)"); |
| |
| // check results are consistent |
| boolean failed = false; |
| if (activeCount != stackTraces.size()) failed = true; |
| if (activeCount != threadCount) failed = true; |
| if (activeCount != threadIds.length) failed = true; |
| |
| if (failed) { |
| throw new RuntimeException("inconsistent results"); |
| } |
| } |
| } |