/* (c) 2014 Open Source Geospatial Foundation - all rights reserved
* (c) 2001 - 2013 OpenPlans
* This code is licensed under the GPL 2.0 license, available at the root
* application directory.
*/
package org.geoserver.cluster;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.PostConstruct;
import org.geoserver.cluster.configuration.JMSConfiguration;
import org.geoserver.cluster.configuration.ToggleConfiguration;
import org.geoserver.cluster.events.ToggleEvent;
import org.geoserver.cluster.events.ToggleType;
import org.geotools.util.logging.Logging;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
/**
*
* This class make it possible to enable and disable the Event producer/consumer using Applications Events.
*
* This is used at the GeoServer startup to disable the producer until the initial configuration is loaded.
*
* It can also be used to enable/disable the producer in a Master+Slave configuration to avoid recursive event production.
*
* @see {@link ToggleEvent}
*
* @author Carlo Cancellieri - carlo.cancellieri@geo-solutions.it
*
*/
public class JMSApplicationListener implements ApplicationListener<ApplicationEvent> {
private final static Logger LOGGER = Logging.getLogger(JMSApplicationListener.class);
protected final ToggleType type;
/**
* This will be set to false:<br/>
* - until the GeoServer context is initialized<br/>
* - if this instance of geoserver act as pure slave
*/
private volatile Boolean status=false;
@Autowired
public JMSConfiguration config;
public JMSApplicationListener(ToggleType type) {
this.type = type;
}
@PostConstruct
private void init(){
setStatus(getStatus(type, config));
}
public static boolean getStatus(final ToggleType type, JMSConfiguration config){
Object statusObj;
if (type.equals(ToggleType.SLAVE)) {
statusObj = config.getConfiguration(ToggleConfiguration.TOGGLE_SLAVE_KEY);
if (statusObj==null){
statusObj=ToggleConfiguration.DEFAULT_SLAVE_STATUS;
}
} else {
statusObj = config.getConfiguration(ToggleConfiguration.TOGGLE_MASTER_KEY);
if (statusObj==null){
statusObj=ToggleConfiguration.DEFAULT_MASTER_STATUS;
}
}
return Boolean.parseBoolean(statusObj.toString());
}
@Override
public void onApplicationEvent(ApplicationEvent event) {
if (LOGGER.isLoggable(Level.FINE)) {
LOGGER.fine("Incoming event of type " + event.getClass().getSimpleName());
}
if (event instanceof ToggleEvent) {
// enable/disable the producer
final ToggleEvent tEv = (ToggleEvent) event;
if (tEv.getType().equals(this.type)) {
setStatus(tEv.toggleTo());
}
} else {
if (LOGGER.isLoggable(Level.FINE)) {
LOGGER.fine("Incoming application event of type "
+ event.getClass().getSimpleName());
}
}
}
/**
* @return the status
*/
public final boolean isEnabled() {
return status;
}
/**
* @param status enable or disable producer
* @note thread safe
*/
public final void setStatus(final boolean producerEnabled) {
if (producerEnabled) {
// if produce is disable -> enable it
if (!this.status) {
synchronized (this.status) {
if (!this.status) {
this.status = true;
}
}
}
} else {
// if produce is Enabled -> disable
if (this.status) {
synchronized (this.status) {
if (this.status) {
this.status = false;
}
}
}
}
}
}