/*
* 2012-3 Red Hat Inc. and/or its affiliates and other contributors.
*
* 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 org.overlord.rtgov.internal.epn.loader.jee;
import static javax.ejb.ConcurrencyManagementType.BEAN;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.ejb.ConcurrencyManagement;
import javax.ejb.Singleton;
import javax.ejb.Startup;
import javax.enterprise.context.ApplicationScoped;
import org.overlord.commons.services.ServiceRegistryUtil;
import org.overlord.rtgov.epn.AbstractEPNLoader;
import org.overlord.rtgov.epn.EPNManager;
import org.overlord.rtgov.epn.Network;
import org.overlord.rtgov.epn.util.NetworkUtil;
/**
* This class provides the capability to load an EPN Network from a
* defined file.
*
*/
@ApplicationScoped
@Singleton
@Startup
@ConcurrencyManagement(BEAN)
public class JEEEPNLoader extends AbstractEPNLoader {
private static final Logger LOG=Logger.getLogger(JEEEPNLoader.class.getName());
private static final String EPN_JSON = "epn.json";
private Network _network=null;
private org.overlord.commons.services.ServiceListener<EPNManager> _listener;
/**
* The constructor.
*/
public JEEEPNLoader() {
}
/**
* This method initializes the EPN loader.
*/
@PostConstruct
public void init() {
_listener = new org.overlord.commons.services.ServiceListener<EPNManager>() {
@Override
public void registered(EPNManager service) {
registerEPN(service);
}
@Override
public void unregistered(EPNManager service) {
unregisterEPN(service);
}
};
ServiceRegistryUtil.addServiceListener(EPNManager.class, _listener);
}
/**
* This method registers the EPN with the EPNManager.
*
* @param epnManager The EPN manager
*/
protected void registerEPN(EPNManager epnManager) {
try {
java.io.InputStream is=Thread.currentThread().getContextClassLoader().getResourceAsStream(EPN_JSON);
if (is == null) {
LOG.severe(java.util.PropertyResourceBundle.getBundle(
"epn-loader-jee.Messages").getString("EPN-LOADER-JEE-1"));
} else {
byte[] b=new byte[is.available()];
is.read(b);
is.close();
_network=NetworkUtil.deserialize(b);
// Pre-initialize the network to avoid any contextual class
// loading issues. Within JEE, the registration of the network
// will be done in the context of the core war, while as the
// event processors require the classloading context associated
// with the network deployment.
preInit(_network);
// TODO: Do we need to halt the deployment due to failures? (RTGOV-199)
epnManager.register(_network);
}
} catch (Exception e) {
String mesg=java.util.PropertyResourceBundle.getBundle(
"epn-loader-jee.Messages").getString("EPN-LOADER-JEE-2");
LOG.log(Level.SEVERE, mesg, e);
// Throw runtime exception to cause the deployment to fail
throw new RuntimeException(mesg, e);
}
}
/**
* This method unregisters the EPN.
*
* @param context The context
*/
protected void unregisterEPN(EPNManager epnManager) {
if (LOG.isLoggable(Level.FINE)) {
LOG.fine("Unregister EPN");
}
if (_network != null) {
try {
epnManager.unregister(_network.getName(), _network.getVersion());
_network = null;
} catch (Throwable t) {
if (LOG.isLoggable(Level.FINER)) {
LOG.log(Level.FINER, java.util.PropertyResourceBundle.getBundle(
"epn-loader-jee.Messages").getString("EPN-LOADER-JEE-3"), t);
}
}
}
}
/**
* This method closes the EPN loader.
*/
@PreDestroy
public void close() {
if (_network != null) {
EPNManager epnManager=ServiceRegistryUtil.getSingleService(EPNManager.class);
if (epnManager != null) {
unregisterEPN(epnManager);
}
}
ServiceRegistryUtil.removeServiceListener(_listener);
_listener = null;
}
}