| /* |
| * Copyright (c) 2011, 2018, 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. |
| */ |
| |
| package nsk.monitoring.ThreadMXBean; |
| |
| import java.util.concurrent.*; |
| |
| /** |
| * Provide synchronization between management thread and its |
| * managed threads. |
| */ |
| public class BarrierHandler { |
| |
| /** |
| * CyclicBarries for internal synchronization |
| */ |
| private CyclicBarrier monitoredThreadsBarrier, startActionBarrier, |
| finishActionBarrier; |
| |
| /** |
| * Creates new BarrierHandler that will match specified Threads with |
| * management threads |
| * |
| * @param threads managed threads that are handled by BarrierHandler |
| */ |
| public BarrierHandler(MXBeanTestThread... threads) { |
| startActionBarrier = new CyclicBarrier(2); |
| finishActionBarrier = new CyclicBarrier(2); |
| monitoredThreadsBarrier = new CyclicBarrier(threads.length, new ActionThread()); |
| } |
| |
| /** |
| * Waits when managed thread completes iteration and some action should |
| * be performed by management thread. Should be called within managed thread |
| * only. |
| * |
| */ |
| public void ready() { |
| try { |
| monitoredThreadsBarrier.await(); |
| } catch (Exception ignored) {} |
| } |
| |
| /** |
| * Allows managed threads to proceed to next iteration. Should be called |
| * within management thread only. |
| */ |
| public void proceed() { |
| try { |
| finishActionBarrier.await(); |
| startActionBarrier.await(); |
| } catch (Exception ignored) {} |
| } |
| |
| /** |
| * Waits until all managed threads complete first iteration. Should be |
| * called within management thread only. |
| */ |
| public void start() { |
| try { |
| startActionBarrier.await(); |
| } catch (Exception ignored) {} |
| } |
| |
| /** |
| * Allows managed threads to finish after last iteration. Should be called |
| * within management thread only. |
| */ |
| public void finish() { |
| try { |
| finishActionBarrier.await(); |
| } catch (Exception ignored) {} |
| } |
| |
| /** |
| * Action performed on main barrier. Used for synchronization between |
| * management and managed threads |
| */ |
| private class ActionThread extends Thread { |
| @Override |
| public void run() { |
| try { |
| startActionBarrier.await(); |
| finishActionBarrier.await(); |
| } catch (Exception ignored) {} |
| } |
| } |
| } |