/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt * or http://forgerock.org/license/CDDLv1.0.html. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at legal-notices/CDDLv1_0.txt. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: * Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END * * * Copyright 2008 Sun Microsystems, Inc. * Portions Copyright 2011-2015 ForgeRock AS */ package org.opends.server.replication.protocol; import java.io.IOException; import org.opends.server.api.DirectoryThread; import org.forgerock.i18n.slf4j.LocalizedLogger; import org.opends.server.util.StaticUtils; /** * This thread publishes a {@link HeartbeatMsg} on a given protocol session at * regular intervals when there are no other replication messages being * published. *
* These heartbeat messages are sent by a replication server. */ public class HeartbeatThread extends DirectoryThread { private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass(); /** * For test purposes only to simulate loss of heartbeats. */ private static volatile boolean heartbeatsDisabled; /** * The session on which heartbeats are to be sent. */ private final Session session; /** * The time in milliseconds between heartbeats. */ private final long heartbeatInterval; /** * Set this to stop the thread. */ private volatile boolean shutdown; private final Object shutdownLock = new Object(); /** * Create a heartbeat thread. * @param threadName The name of the heartbeat thread. * @param session The session on which heartbeats are to be sent. * @param heartbeatInterval The desired interval between heartbeats in * milliseconds. */ public HeartbeatThread(String threadName, Session session, long heartbeatInterval) { super(threadName); this.session = session; this.heartbeatInterval = heartbeatInterval; } /** {@inheritDoc} */ @Override public void run() { try { if (logger.isTraceEnabled()) { logger.trace("Heartbeat thread is starting, interval is %d", heartbeatInterval); } HeartbeatMsg heartbeatMessage = new HeartbeatMsg(); while (!shutdown) { long now = System.currentTimeMillis(); if (logger.isTraceEnabled()) { logger.trace("Heartbeat thread awoke at %d, last message " + "was sent at %d", now, session.getLastPublishTime()); } if (now > session.getLastPublishTime() + heartbeatInterval && !heartbeatsDisabled) { if (logger.isTraceEnabled()) { logger.trace("Heartbeat sent at %d", now); } session.publish(heartbeatMessage); } long sleepTime = session.getLastPublishTime() + heartbeatInterval - now; if (sleepTime <= 0) { sleepTime = heartbeatInterval; } if (logger.isTraceEnabled()) { logger.trace("Heartbeat thread sleeping for %d", sleepTime); } synchronized (shutdownLock) { if (!shutdown) { try { shutdownLock.wait(sleepTime); } catch (InterruptedException e) { // Server shutdown monitor may interrupt slow threads. logger.traceException(e); shutdown = true; } } } } } catch (IOException e) { if (logger.isTraceEnabled()) { logger.trace("Heartbeat thread could not send a heartbeat." + StaticUtils.stackTraceToSingleLineString(e)); } } finally { if (logger.isTraceEnabled()) { logger.trace("Heartbeat thread is exiting."); } } } /** * Call this method to stop the thread. * This method is blocking until the thread has stopped. */ public void shutdown() { synchronized (shutdownLock) { shutdown = true; shutdownLock.notifyAll(); if (logger.isTraceEnabled()) { logger.trace("Going to notify Heartbeat thread."); } } if (logger.isTraceEnabled()) { logger.trace("Returning from Heartbeat shutdown."); } } /** * For testing purposes only to simulate loss of heartbeats. * @param heartbeatsDisabled Set true to prevent heartbeats from being sent. */ public static void setHeartbeatsDisabled(boolean heartbeatsDisabled) { HeartbeatThread.heartbeatsDisabled = heartbeatsDisabled; } }