/*
* 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.mina.core.session;
import java.util.Iterator;
import java.util.Set;
import org.apache.mina.core.future.CloseFuture;
import org.apache.mina.core.future.IoFuture;
import org.apache.mina.core.future.IoFutureListener;
import org.apache.mina.core.service.IoService;
import org.apache.mina.util.ConcurrentHashSet;
/**
* Detects idle sessions and fires <tt>sessionIdle</tt> events to them.
* To be used for service unable to trigger idle events alone, like VmPipe
* or SerialTransport. Polling base transport are advised to trigger idle
* events alone, using the poll/select timeout.
*
* @author The Apache MINA Project (dev@mina.apache.org)
* @version $Rev: 525369 $, $Date: 2007-04-04 05:05:11 +0200 (mer., 04 avr. 2007) $
*/
public class IdleStatusChecker {
// the list of session to check
private final Set<AbstractIoSession> sessions =
new ConcurrentHashSet<AbstractIoSession>();
/* create a task you can execute in the transport code,
* if the transport is like NIO or APR you don't need to call it,
* you just need to call the needed static sessions on select()/poll()
* timeout.
*/
private final NotifyingTask notifyingTask = new NotifyingTask();
private final IoFutureListener<IoFuture> sessionCloseListener =
new SessionCloseListener();
public IdleStatusChecker() {}
/**
* Add the session for being checked for idle.
* @param session the session to check
*/
public void addSession(AbstractIoSession session) {
sessions.add(session);
CloseFuture closeFuture = session.getCloseFuture();
// isn't service reponsability to remove the session nicely ?
closeFuture.addListener(sessionCloseListener);
}
/**
* remove a session from the list of session being checked.
* @param session
*/
private void removeSession(AbstractIoSession session) {
sessions.remove(session);
}
/**
* get a runnable task able to be scheduled in the {@link IoService} executor.
* @return
*/
public NotifyingTask getNotifyingTask() {
return notifyingTask;
}
/**
* The class to place in the transport executor for checking the sessions idle
*/
public class NotifyingTask implements Runnable {
private volatile boolean cancelled;
private volatile Thread thread;
// we forbid instantiation of this class outside
private NotifyingTask() {
}
public void run() {
thread = Thread.currentThread();
try {
while (!cancelled) {
// Check idleness with fixed delay (1 second).
long currentTime = System.currentTimeMillis();
notifySessions(currentTime);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// will exit the loop if interrupted from interrupt()
}
}
} finally {
thread = null;
}
}
/**
* stop execution of the task
*/
public void cancel() {
cancelled = true;
Thread thread = this.thread;
if (thread != null) {
thread.interrupt();
}
}
private void notifySessions(long currentTime) {
Iterator<AbstractIoSession> it = sessions.iterator();
while (it.hasNext()) {
AbstractIoSession session = it.next();
if (session.isConnected()) {
AbstractIoSession.notifyIdleSession(session, currentTime);
}
}
}
}
private class SessionCloseListener implements IoFutureListener<IoFuture> {
public void operationComplete(IoFuture future) {
removeSession((AbstractIoSession) future.getSession());
}
}
}