/*
* Copyright 2009-2012 the original author or authors.
*
* 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.cloudfoundry.caldecott.client;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.cloudfoundry.caldecott.TunnelException;
import org.springframework.core.task.TaskExecutor;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.net.SocketTimeoutException;
import java.util.Observable;
import java.util.Observer;
import java.util.concurrent.ConcurrentHashMap;
/**
* The class responsible for listening for client connection attempts and handing off to
* a TunnelHandler for handling the actual tunneling communications.
*
* @author Thomas Risberg
*/
public class TunnelAcceptor implements Runnable {
public static final int SOCKET_TIMEOUT = 10000;
protected final Log logger = LogFactory.getLog(getClass());
// configuration options
private final TunnelFactory tunnelFactory;
private final ServerSocket serverSocket;
private final TaskExecutor taskExecutor;
// variable to keep acceptor active
// this is volatile since it can we altered by another thread via stop()
private volatile boolean keepGoing = true;
// concurrent map to keep track of handlers, will be modified from handler threads
private ConcurrentHashMap<TunnelHandler, Boolean> handlers = new ConcurrentHashMap<TunnelHandler, Boolean>();
public TunnelAcceptor(ServerSocket serverSocket, TunnelFactory tunnelFactory, TaskExecutor taskExecutor) {
this.serverSocket = serverSocket;
this.tunnelFactory = tunnelFactory;
this.taskExecutor = taskExecutor;
try {
this.serverSocket.setSoTimeout(SOCKET_TIMEOUT);
} catch (SocketException ignore) {}
}
public void start() {
logger.info("Starting new acceptor thread: " + this);
taskExecutor.execute(this);
logger.debug("Completed start of: " + taskExecutor);
}
public boolean isActive() {
return handlers.size() > 0;
}
public void stop() {
logger.info("Stop requested for: " + this);
keepGoing = false;
}
public void run() {
while (keepGoing) {
try {
logger.trace("Waiting for client connection");
Socket sourceSocket = serverSocket.accept();
logger.debug("Accepted client connection");
TunnelHandler handler = new TunnelHandler(sourceSocket, tunnelFactory, taskExecutor);
handler.addObserver(new Observer() {
public void update(Observable observable, Object o) {
if (logger.isDebugEnabled()) {
logger.debug("Notified that " + observable + " is now " + o);
}
handlers.remove(observable);
}
});
handlers.put(handler, true);
handler.start();
}
catch (SocketTimeoutException ste) {}
catch (IOException e) {
if (!keepGoing && serverSocket.isClosed()) {
// time to quit so we can ignore this exception
}
else {
throw new TunnelException("Error while accepting connections", e);
}
}
}
if (!handlers.isEmpty()) {
while (!handlers.isEmpty()) {
logger.debug("Waiting for " + handlers.size() + " client connections to close");
for (TunnelHandler handler : handlers.keySet()) {
logger.debug("Poking " + handler);
handler.poke();
}
try {
Thread.sleep(10000);
} catch (InterruptedException ignore) {}
}
}
logger.info("Completed acceptor thread for: " + this);
}
}