//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.websocket.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.websocket.api.WebSocketBehavior;
import org.eclipse.jetty.websocket.api.WebSocketPolicy;
/**
* Abstract Servlet used to bridge the Servlet API to the WebSocket API.
* <p>
* To use this servlet, you will be required to register your websockets with the {@link WebSocketServletFactory} so that it can create your websockets under the
* appropriate conditions.
* <p>
* The most basic implementation would be as follows.
*
* <pre>
* package my.example;
*
* import org.eclipse.jetty.websocket.servlet.WebSocketServlet;
* import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
*
* public class MyEchoServlet extends WebSocketServlet
* {
* @Override
* public void configure(WebSocketServletFactory factory)
* {
* // set a 10 second idle timeout
* factory.getPolicy().setIdleTimeout(10000);
* // register my socket
* factory.register(MyEchoSocket.class);
* }
* }
* </pre>
*
* Note: that only request that conforms to a "WebSocket: Upgrade" handshake request will trigger the {@link WebSocketServletFactory} handling of creating
* WebSockets.<br>
* All other requests are treated as normal servlet requests.
*
* <p>
* <b>Configuration / Init-Parameters:</b><br>
* Note: If you use the {@link WebSocket @WebSocket} annotation, these configuration settings can be specified on a per WebSocket basis, vs a per Servlet
* basis.
*
* <dl>
* <dt>maxIdleTime</dt>
* <dd>set the time in ms that a websocket may be idle before closing<br>
*
* <dt>maxTextMessageSize</dt>
* <dd>set the size in UTF-8 bytes that a websocket may be accept as a Text Message before closing<br>
*
* <dt>maxBinaryMessageSize</dt>
* <dd>set the size in bytes that a websocket may be accept as a Binary Message before closing<br>
*
* <dt>inputBufferSize</dt>
* <dd>set the size in bytes of the buffer used to read raw bytes from the network layer<br>
* </dl>
*/
@SuppressWarnings("serial")
public abstract class WebSocketServlet extends HttpServlet
{
private WebSocketServletFactory factory;
public abstract void configure(WebSocketServletFactory factory);
@Override
public void destroy()
{
factory.cleanup();
}
/**
* @see javax.servlet.GenericServlet#init()
*/
@Override
public void init() throws ServletException
{
try
{
WebSocketPolicy policy = new WebSocketPolicy(WebSocketBehavior.SERVER);
String max = getInitParameter("maxIdleTime");
if (max != null)
{
policy.setIdleTimeout(Long.parseLong(max));
}
max = getInitParameter("maxTextMessageSize");
if (max != null)
{
policy.setMaxTextMessageSize(Integer.parseInt(max));
}
max = getInitParameter("maxBinaryMessageSize");
if (max != null)
{
policy.setMaxBinaryMessageSize(Integer.parseInt(max));
}
max = getInitParameter("inputBufferSize");
if (max != null)
{
policy.setInputBufferSize(Integer.parseInt(max));
}
factory = WebSocketServletFactory.Loader.create(policy);
configure(factory);
factory.init();
}
catch (Exception x)
{
throw new ServletException(x);
}
}
/**
* @see javax.servlet.http.HttpServlet#service(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
@Override
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
if (factory.isUpgradeRequest(request,response))
{
// We have an upgrade request
if (factory.acceptWebSocket(request,response))
{
// We have a socket instance created
return;
}
// If we reach this point, it means we had an incoming request to upgrade
// but it was either not a proper websocket upgrade, or it was possibly rejected
// due to incoming request constraints (controlled by WebSocketCreator)
if (response.isCommitted())
{
// not much we can do at this point.
return;
}
}
// All other processing
super.service(request,response);
}
}