net.roboconf.agent.monitoring.internal.AgentMonitoring Maven / Gradle / Ivy
/**
* Copyright 2014-2016 Linagora, Université Joseph Fourier, Floralis
*
* The present code is developed in the scope of the joint LINAGORA -
* Université Joseph Fourier - Floralis research program and is designated
* as a "Result" pursuant to the terms and conditions of the LINAGORA
* - Université Joseph Fourier - Floralis research program. Each copyright
* holder of Results enumerated here above fully & independently holds complete
* ownership of the complete Intellectual Property rights applicable to the whole
* of said Results, and may freely exploit it in any manner which does not infringe
* the moral rights of the other copyright holders.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.roboconf.agent.monitoring.internal;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;
import net.roboconf.agent.AgentMessagingInterface;
import net.roboconf.agent.monitoring.api.IMonitoringHandler;
import net.roboconf.agent.monitoring.internal.file.FileHandler;
import net.roboconf.agent.monitoring.internal.nagios.NagiosHandler;
import net.roboconf.agent.monitoring.internal.rest.RestHandler;
import net.roboconf.core.Constants;
/**
* The agent monitoring service.
* @author Pierre-Yves Gibello - Linagora
*/
public class AgentMonitoring {
// Injected by iPojo
private AgentMessagingInterface agentInterface;
private final List handlers = new ArrayList<> ();
// Internal fields
private final Logger logger = Logger.getLogger( getClass().getName());
private ScheduledThreadPoolExecutor timer;
/**
* Constructor.
*/
public AgentMonitoring() {
// Register predefined monitoring handlers
handlerAppears( new FileHandler());
handlerAppears( new NagiosHandler());
handlerAppears( new RestHandler());
}
/**
* Starts the POJO (invoked by iPojo).
*/
public void start() {
if( this.timer == null ) {
this.logger.fine( "Agent Monitoring is being started." );
this.timer = new ScheduledThreadPoolExecutor( 1 );
this.timer.scheduleWithFixedDelay(
new MonitoringRunnable( this.agentInterface, this.handlers ),
0, Constants.PROBES_POLLING_PERIOD, TimeUnit.MILLISECONDS );
}
}
/**
* Stops the POJO (invoked by iPojo).
*/
public void stop() {
this.logger.fine( "Agent Monitoring is being stopped." );
if( this.timer != null ) {
this.timer.shutdownNow();
this.timer = null;
}
}
/**
* This method is invoked by iPojo every time a new monitoring handler appears.
* @param handler the appearing monitoring handler
*/
public void handlerAppears( IMonitoringHandler handler ) {
if( handler != null ) {
this.logger.info( "Monitoring handler '" + handler.getName() + "' is now available." );
this.handlers.add( handler );
listHandlers( this.handlers, this.logger );
}
}
/**
* This method is invoked by iPojo every time a monitoring handler disappears.
* @param handler the disappearing monitoring handler
*/
public void handlerDisappears( IMonitoringHandler handler ) {
// May happen if a target could not be instantiated
// (iPojo uses proxies). In this case, it results in a NPE here.
if( handler == null ) {
this.logger.info( "An invalid monitoring handler is removed." );
} else {
this.handlers.remove( handler );
this.logger.info( "Monitoring handler '" + handler.getName() + "' is not available anymore." );
}
listHandlers( this.handlers, this.logger );
}
/**
* Force injection of agentInterface field (for tests: normally injected by iPojo).
* @param agentInterface
*/
public void setAgentInterface( AgentMessagingInterface agentInterface ) {
this.agentInterface = agentInterface;
}
/**
* This method lists the available handlers and logs them.
*/
public static void listHandlers( List handlers, Logger logger ) {
if( handlers.isEmpty()) {
logger.info( "No monitoring handler was found." );
} else {
StringBuilder sb = new StringBuilder( "Available monitoring handlers: " );
for( Iterator it = handlers.iterator(); it.hasNext(); ) {
sb.append( it.next().getName());
if( it.hasNext())
sb.append( ", " );
}
sb.append( "." );
logger.info( sb.toString());
}
}
}