/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.openejb.server.ejbd;
import org.apache.openejb.client.ClusterMetaData;
import org.apache.openejb.client.ClusterRequest;
import org.apache.openejb.client.ClusterResponse;
import org.apache.openejb.client.ProtocolMetaData;
import org.apache.openejb.client.Response;
import org.apache.openejb.server.DiscoveryListener;
import org.apache.openejb.util.Join;
import org.apache.openejb.util.LogCategory;
import org.apache.openejb.util.Logger;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
* @version $Rev$ $Date$
*/
public class ClusterRequestHandler extends RequestHandler implements DiscoveryListener {
private static final Logger logger = Logger.getInstance(LogCategory.OPENEJB_SERVER_REMOTE.createChild("cluster"), ClusterRequestHandler.class);
private final Data data = new Data();
public ClusterRequestHandler(final EjbDaemon daemon) {
super(daemon);
}
@Override
public Logger getLogger() {
return logger;
}
@Override
public ClusterResponse processRequest(final ObjectInputStream in, final ProtocolMetaData metaData) throws Exception {
final ClusterRequest req = new ClusterRequest();
req.setMetaData(metaData);
final ClusterResponse res = new ClusterResponse();
res.setMetaData(metaData);
try {
req.readExternal(in);
} catch (IOException e) {
res.setFailure(e);
return res;
} catch (ClassNotFoundException e) {
res.setFailure(new IOException().initCause(e));
return res;
}
final ClusterMetaData currentClusterMetaData = data.current();
if (req.getClusterMetaDataVersion() < currentClusterMetaData.getVersion()) {
if (logger.isDebugEnabled()) {
final URI[] locations = currentClusterMetaData.getLocations();
if (locations.length < 10) {
logger.debug("Sending client updated cluster locations: [" + Join.join(", ", locations) + "]");
} else {
logger.debug("Sending client updated cluster locations: " + locations.length + " locations total");
}
}
res.setUpdatedMetaData(currentClusterMetaData);
} else {
res.setCurrent();
}
return res;
}
@Override
public String getName() {
return "Cluster";
}
@Override
public void processResponse(final Response response, final ObjectOutputStream out, final ProtocolMetaData metaData) throws Exception {
if (null != response) {
if (ClusterResponse.class.isInstance(response)) {
final ClusterResponse res = (ClusterResponse) response;
try {
res.setMetaData(metaData);
res.writeExternal(out);
} catch (IOException e) {
logger.error("Failed to write to ClusterResponse", e);
throw e;
}
} else {
logger.error("ClusterRequestHandler cannot process an instance of: " + response.getClass().getName());
}
}
}
@Override
public void serviceAdded(final URI uri) {
try {
final URI service = unwrap(uri);
if ("ejb".equals(uri.getScheme())) {
logger.info("Peer discovered: " + service.toString());
data.add(service);
}
} catch (URISyntaxException e) {
logger.error("serviceAdded: Invalid service URI format. Expected <group>:<type>:<serverURI> but found '" + uri.toString() + "'");
}
}
private URI unwrap(final URI uri) throws URISyntaxException {
return new URI(uri.getSchemeSpecificPart());
}
@Override
public void serviceRemoved(final URI uri) {
try {
final URI service = unwrap(uri);
if ("ejb".equals(uri.getScheme())) {
logger.info("Peer removed: " + service.toString());
data.remove(service);
}
} catch (URISyntaxException e) {
logger.error("serviceAdded: Invalid service URI format. Expected <group>:<type>:<serverURI> but found '" + uri.toString() + "'");
}
}
private static class Data {
private final AtomicReference<ClusterMetaData> current = new AtomicReference<ClusterMetaData>();
private final ReadWriteLock sync = new ReentrantReadWriteLock();
private final java.util.Set set = new LinkedHashSet();
public Data() {
this.current.set(new ClusterMetaData(0));
}
@SuppressWarnings("unchecked")
public boolean add(final URI o) {
final Lock lock = sync.writeLock();
lock.lock();
try {
ClusterMetaData nextVersion = null;
try {
if (set.add(o)) {
nextVersion = newClusterMetaData(set, current.get());
return true;
} else {
return false;
}
} finally {
if (nextVersion != null) {
current.set(nextVersion);
}
}
} finally {
lock.unlock();
}
}
public boolean remove(final Object o) {
final Lock lock = sync.writeLock();
lock.lock();
try {
ClusterMetaData nextVersion = null;
try {
if (set.remove(o)) {
nextVersion = newClusterMetaData(set, current.get());
return true;
} else {
return false;
}
} finally {
if (nextVersion != null) {
current.set(nextVersion);
}
}
} finally {
lock.unlock();
}
}
private static ClusterMetaData newClusterMetaData(final Set set, final ClusterMetaData current) {
final URI[] locations = new URI[set.size()];
set.toArray(locations);
return new ClusterMetaData(System.currentTimeMillis(), locations);
}
public ClusterMetaData current() {
final Lock lock = sync.readLock();
lock.lock();
try {
return current.get();
} finally {
lock.unlock();
}
}
}
}