org.eclipse.jetty.continuation.Servlet3Continuation Maven / Gradle / Ivy
//
// ========================================================================
// 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.continuation;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
import javax.servlet.DispatcherType;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.ServletResponseWrapper;
/* ------------------------------------------------------------ */
/**
* This implementation of Continuation is used by {@link ContinuationSupport}
* when it detects that the application has been deployed in a non-jetty Servlet 3
* server.
*/
public class Servlet3Continuation implements Continuation
{
// Exception reused for all continuations
// Turn on debug in ContinuationFilter to see real stack trace.
private final static ContinuationThrowable __exception = new ContinuationThrowable();
private final ServletRequest _request;
private ServletResponse _response;
private AsyncContext _context;
private List _listeners=new ArrayList();
private volatile boolean _initial=true;
private volatile boolean _resumed=false;
private volatile boolean _expired=false;
private volatile boolean _responseWrapped=false;
private long _timeoutMs=-1;
/* ------------------------------------------------------------ */
public Servlet3Continuation(ServletRequest request)
{
_request=request;
_listeners.add(new AsyncListener()
{
public void onComplete(AsyncEvent event) throws IOException
{
}
public void onError(AsyncEvent event) throws IOException
{
}
public void onStartAsync(AsyncEvent event) throws IOException
{
event.getAsyncContext().addListener(this);
}
public void onTimeout(AsyncEvent event) throws IOException
{
_initial=false;
event.getAsyncContext().dispatch();
}
});
}
/* ------------------------------------------------------------ */
public void addContinuationListener(final ContinuationListener listener)
{
AsyncListener wrapped = new AsyncListener()
{
public void onComplete(final AsyncEvent event) throws IOException
{
listener.onComplete(Servlet3Continuation.this);
}
public void onError(AsyncEvent event) throws IOException
{
listener.onComplete(Servlet3Continuation.this);
}
public void onStartAsync(AsyncEvent event) throws IOException
{
event.getAsyncContext().addListener(this);
}
public void onTimeout(AsyncEvent event) throws IOException
{
_expired=true;
listener.onTimeout(Servlet3Continuation.this);
}
};
if (_context!=null)
_context.addListener(wrapped);
else
_listeners.add(wrapped);
}
/* ------------------------------------------------------------ */
public void complete()
{
AsyncContext context=_context;
if (context==null)
throw new IllegalStateException();
_context.complete();
}
/* ------------------------------------------------------------ */
public ServletResponse getServletResponse()
{
return _response;
}
/* ------------------------------------------------------------ */
public boolean isExpired()
{
return _expired;
}
/* ------------------------------------------------------------ */
public boolean isInitial()
{
// TODO - this is not perfect if non continuation API is used directly
return _initial&&_request.getDispatcherType()!=DispatcherType.ASYNC;
}
/* ------------------------------------------------------------ */
public boolean isResumed()
{
return _resumed;
}
/* ------------------------------------------------------------ */
public boolean isSuspended()
{
return _request.isAsyncStarted();
}
/* ------------------------------------------------------------ */
public void keepWrappers()
{
_responseWrapped=true;
}
/* ------------------------------------------------------------ */
public void resume()
{
AsyncContext context=_context;
if (context==null)
throw new IllegalStateException();
_resumed=true;
_context.dispatch();
}
/* ------------------------------------------------------------ */
public void setTimeout(long timeoutMs)
{
_timeoutMs=timeoutMs;
if (_context!=null)
_context.setTimeout(timeoutMs);
}
/* ------------------------------------------------------------ */
public void suspend(ServletResponse response)
{
_response=response;
_responseWrapped=response instanceof ServletResponseWrapper;
_resumed=false;
_expired=false;
_context=_request.startAsync();
_context.setTimeout(_timeoutMs);
for (AsyncListener listener:_listeners)
_context.addListener(listener);
_listeners.clear();
}
/* ------------------------------------------------------------ */
public void suspend()
{
_resumed=false;
_expired=false;
_context=_request.startAsync();
_context.setTimeout(_timeoutMs);
for (AsyncListener listener:_listeners)
_context.addListener(listener);
_listeners.clear();
}
/* ------------------------------------------------------------ */
public boolean isResponseWrapped()
{
return _responseWrapped;
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#getAttribute(java.lang.String)
*/
public Object getAttribute(String name)
{
return _request.getAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#removeAttribute(java.lang.String)
*/
public void removeAttribute(String name)
{
_request.removeAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#setAttribute(java.lang.String, java.lang.Object)
*/
public void setAttribute(String name, Object attribute)
{
_request.setAttribute(name,attribute);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#undispatch()
*/
public void undispatch()
{
if (isSuspended())
{
if (ContinuationFilter.__debug)
throw new ContinuationThrowable();
throw __exception;
}
throw new IllegalStateException("!suspended");
}
}