/*
* Copyright 2010 Richard Zschech.
*
* 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 net.zschech.gwt.comet.server.impl;
import java.io.IOException;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
import javax.servlet.http.HttpServletRequest;
public class Servlet30AsyncServlet extends NonBlockingAsyncServlet {
@Override
public Object suspend(final CometServletResponseImpl response, CometSessionImpl session, HttpServletRequest request) throws IOException {
assert Thread.holdsLock(response);
assert session == null || !Thread.holdsLock(session);
response.flush();
AsyncContext asyncContext = request.startAsync();
asyncContext.addListener(new AsyncListener() {
@Override
public void onStartAsync(AsyncEvent e) throws IOException {
}
@Override
public void onComplete(AsyncEvent e) throws IOException {
}
@Override
public void onTimeout(AsyncEvent e) throws IOException {
onError(e);
}
@Override
public void onError(AsyncEvent e) throws IOException {
synchronized (response) {
if (!response.isTerminated()) {
response.setTerminated(false);
}
}
}
});
asyncContext.setTimeout(Long.MAX_VALUE);
write(response, session);
return asyncContext;
}
@Override
public void terminate(CometServletResponseImpl response, CometSessionImpl session, boolean serverInitiated, Object suspendInfo) {
assert Thread.holdsLock(response);
assert session == null || !Thread.holdsLock(session);
if (serverInitiated && suspendInfo != null) {
AsyncContext asyncContext = (AsyncContext) suspendInfo;
asyncContext.complete();
}
}
@Override
public void enqueued(CometSessionImpl session) {
final CometServletResponseImpl response = session.getResponse();
if (response != null) {
synchronized (response) {
write(response, session);
}
}
}
@Override
public void invalidate(CometSessionImpl session) {
final CometServletResponseImpl response = session.getResponse();
if (response != null) {
response.tryTerminate();
}
}
private void write(final CometServletResponseImpl response, final CometSessionImpl session) {
assert Thread.holdsLock(response);
if (!session.isEmpty()) {
final AsyncContext asyncContext = (AsyncContext) response.getSuspendInfo();
asyncContext.start(new Runnable() {
@Override
public void run() {
synchronized (response) {
try {
session.writeQueue(response, true);
}
catch (IOException e) {
log("Error writing session messages");
}
if (!session.isEmpty()) {
asyncContext.start(this);
}
}
}
});
}
}
}