// ========================================================================
// Copyright (c) 2007-2009 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.server;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import org.eclipse.jetty.continuation.Continuation;
import org.eclipse.jetty.continuation.ContinuationListener;
import org.eclipse.jetty.continuation.ContinuationThrowable;
import org.eclipse.jetty.io.AsyncEndPoint;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.server.handler.ContextHandler;
import org.eclipse.jetty.server.handler.ContextHandler.Context;
import org.eclipse.jetty.util.URIUtil;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
import org.eclipse.jetty.util.thread.Timeout;
/* ------------------------------------------------------------ */
/** Implementation of Continuation and AsyncContext interfaces.
*
*/
public class AsyncContinuation implements AsyncContext, Continuation
{
private static final Logger LOG = Log.getLogger(AsyncContinuation.class);
private final static long DEFAULT_TIMEOUT=30000L;
private final static ContinuationThrowable __exception = new ContinuationThrowable();
// STATES:
// handling() suspend() unhandle() resume() complete() doComplete()
// startAsync() dispatch()
// IDLE DISPATCHED
// DISPATCHED ASYNCSTARTED UNCOMPLETED
// ASYNCSTARTED ASYNCWAIT REDISPATCHING COMPLETING
// REDISPATCHING REDISPATCHED
// ASYNCWAIT REDISPATCH COMPLETING
// REDISPATCH REDISPATCHED
// REDISPATCHED ASYNCSTARTED UNCOMPLETED
// COMPLETING UNCOMPLETED UNCOMPLETED
// UNCOMPLETED COMPLETED
// COMPLETED
private static final int __IDLE=0; // Idle request
private static final int __DISPATCHED=1; // Request dispatched to filter/servlet
private static final int __ASYNCSTARTED=2; // Suspend called, but not yet returned to container
private static final int __REDISPATCHING=3;// resumed while dispatched
private static final int __ASYNCWAIT=4; // Suspended and parked
private static final int __REDISPATCH=5; // Has been scheduled
private static final int __REDISPATCHED=6; // Request redispatched to filter/servlet
private static final int __COMPLETING=7; // complete while dispatched
private static final int __UNCOMPLETED=8; // Request is completable
private static final int __COMPLETED=9; // Request is complete
/* ------------------------------------------------------------ */
protected AbstractHttpConnection _connection;
private List<ContinuationListener> _continuationListeners;
/* ------------------------------------------------------------ */
private int _state;
private boolean _initial;
private boolean _resumed;
private boolean _expired;
private volatile boolean _responseWrapped;
private long _timeoutMs=DEFAULT_TIMEOUT;
private AsyncEventState _event;
private volatile long _expireAt;
/* ------------------------------------------------------------ */
protected AsyncContinuation()
{
_state=__IDLE;
_initial=true;
}
/* ------------------------------------------------------------ */
protected void setConnection(final AbstractHttpConnection connection)
{
synchronized(this)
{
_connection=connection;
}
}
/* ------------------------------------------------------------ */
public void addContinuationListener(ContinuationListener listener)
{
synchronized(this)
{
if (_continuationListeners==null)
_continuationListeners=new ArrayList<ContinuationListener>();
_continuationListeners.add(listener);
}
}
/* ------------------------------------------------------------ */
public void setTimeout(long ms)
{
synchronized(this)
{
_timeoutMs=ms;
}
}
/* ------------------------------------------------------------ */
public long getTimeout()
{
synchronized(this)
{
return _timeoutMs;
}
}
/* ------------------------------------------------------------ */
public AsyncEventState getAsyncEventState()
{
synchronized(this)
{
return _event;
}
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#keepWrappers()
*/
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#isResponseWrapped()
*/
public boolean isResponseWrapped()
{
return _responseWrapped;
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#isInitial()
*/
public boolean isInitial()
{
synchronized(this)
{
return _initial;
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#isSuspended()
*/
public boolean isSuspended()
{
synchronized(this)
{
switch(_state)
{
case __ASYNCSTARTED:
case __REDISPATCHING:
case __COMPLETING:
case __ASYNCWAIT:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
public boolean isSuspending()
{
synchronized(this)
{
switch(_state)
{
case __ASYNCSTARTED:
case __ASYNCWAIT:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
public boolean isDispatchable()
{
synchronized(this)
{
switch(_state)
{
case __REDISPATCH:
case __REDISPATCHED:
case __REDISPATCHING:
case __COMPLETING:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
@Override
public String toString()
{
synchronized (this)
{
return super.toString()+"@"+getStatusString();
}
}
/* ------------------------------------------------------------ */
public String getStatusString()
{
synchronized (this)
{
return
((_state==__IDLE)?"IDLE":
(_state==__DISPATCHED)?"DISPATCHED":
(_state==__ASYNCSTARTED)?"ASYNCSTARTED":
(_state==__ASYNCWAIT)?"ASYNCWAIT":
(_state==__REDISPATCHING)?"REDISPATCHING":
(_state==__REDISPATCH)?"REDISPATCH":
(_state==__REDISPATCHED)?"REDISPATCHED":
(_state==__COMPLETING)?"COMPLETING":
(_state==__UNCOMPLETED)?"UNCOMPLETED":
(_state==__COMPLETED)?"COMPLETE":
("UNKNOWN?"+_state))+
(_initial?",initial":"")+
(_resumed?",resumed":"")+
(_expired?",expired":"");
}
}
/* ------------------------------------------------------------ */
/**
* @return false if the handling of the request should not proceed
*/
protected boolean handling()
{
synchronized (this)
{
_responseWrapped=false;
switch(_state)
{
case __IDLE:
_initial=true;
_state=__DISPATCHED;
return true;
case __COMPLETING:
_state=__UNCOMPLETED;
return false;
case __ASYNCWAIT:
return false;
case __REDISPATCH:
_state=__REDISPATCHED;
return true;
default:
throw new IllegalStateException(this.getStatusString());
}
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#suspend(long)
*/
private void doSuspend(final ServletContext context,
final ServletRequest request,
final ServletResponse response)
{
synchronized (this)
{
switch(_state)
{
case __DISPATCHED:
case __REDISPATCHED:
_resumed=false;
_expired=false;
if (_event==null || request!=_event.getRequest() || response != _event.getResponse() || context != _event.getServletContext())
_event=new AsyncEventState(context,request,response);
else
{
_event._dispatchContext=null;
_event._pathInContext=null;
}
_state=__ASYNCSTARTED;
break;
default:
throw new IllegalStateException(this.getStatusString());
}
}
}
/* ------------------------------------------------------------ */
/**
* Signal that the HttpConnection has finished handling the request.
* For blocking connectors, this call may block if the request has
* been suspended (startAsync called).
* @return true if handling is complete, false if the request should
* be handled again (eg because of a resume that happened before unhandle was called)
*/
protected boolean unhandle()
{
synchronized (this)
{
List<ContinuationListener> listeners=_continuationListeners;
switch(_state)
{
case __REDISPATCHED:
case __DISPATCHED:
_state=__UNCOMPLETED;
return true;
case __IDLE:
throw new IllegalStateException(this.getStatusString());
case __ASYNCSTARTED:
_initial=false;
_state=__ASYNCWAIT;
scheduleTimeout(); // could block and change state.
if (_state==__ASYNCWAIT)
return true;
else if (_state==__COMPLETING)
{
_state=__UNCOMPLETED;
return true;
}
_initial=false;
_state=__REDISPATCHED;
return false;
case __REDISPATCHING:
_initial=false;
_state=__REDISPATCHED;
return false;
case __COMPLETING:
_initial=false;
_state=__UNCOMPLETED;
return true;
default:
throw new IllegalStateException(this.getStatusString());
}
}
}
/* ------------------------------------------------------------ */
public void dispatch()
{
boolean dispatch=false;
synchronized (this)
{
switch(_state)
{
case __ASYNCSTARTED:
_state=__REDISPATCHING;
_resumed=true;
return;
case __ASYNCWAIT:
dispatch=!_expired;
_state=__REDISPATCH;
_resumed=true;
break;
case __REDISPATCH:
return;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (dispatch)
{
cancelTimeout();
scheduleDispatch();
}
}
/* ------------------------------------------------------------ */
protected void expired()
{
final List<ContinuationListener> listeners;
synchronized (this)
{
switch(_state)
{
case __ASYNCSTARTED:
case __ASYNCWAIT:
listeners=_continuationListeners;
break;
default:
listeners=null;
return;
}
_expired=true;
}
if (listeners!=null)
{
for (int i=0;i<listeners.size();i++)
{
ContinuationListener listener=listeners.get(i);
try
{
listener.onTimeout(this);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
synchronized (this)
{
switch(_state)
{
case __ASYNCSTARTED:
case __ASYNCWAIT:
dispatch();
}
}
scheduleDispatch();
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#complete()
*/
public void complete()
{
// just like resume, except don't set _resumed=true;
boolean dispatch=false;
synchronized (this)
{
switch(_state)
{
case __DISPATCHED:
case __REDISPATCHED:
throw new IllegalStateException(this.getStatusString());
case __ASYNCSTARTED:
_state=__COMPLETING;
return;
case __ASYNCWAIT:
_state=__COMPLETING;
dispatch=!_expired;
break;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (dispatch)
{
cancelTimeout();
scheduleDispatch();
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#complete()
*/
protected void doComplete()
{
final List<ContinuationListener> listeners;
synchronized (this)
{
switch(_state)
{
case __UNCOMPLETED:
_state=__COMPLETED;
listeners=_continuationListeners;
break;
default:
listeners=null;
throw new IllegalStateException(this.getStatusString());
}
}
if (listeners!=null)
{
for(int i=0;i<listeners.size();i++)
{
try
{
listeners.get(i).onComplete(this);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
}
/* ------------------------------------------------------------ */
protected void recycle()
{
synchronized (this)
{
// _history.append("r\n");
switch(_state)
{
case __DISPATCHED:
case __REDISPATCHED:
throw new IllegalStateException(getStatusString());
default:
_state=__IDLE;
}
_initial = true;
_resumed=false;
_expired=false;
_responseWrapped=false;
cancelTimeout();
_timeoutMs=DEFAULT_TIMEOUT;
_continuationListeners=null;
}
}
/* ------------------------------------------------------------ */
public void cancel()
{
synchronized (this)
{
cancelTimeout();
_continuationListeners=null;
}
}
/* ------------------------------------------------------------ */
protected void scheduleDispatch()
{
EndPoint endp=_connection.getEndPoint();
if (!endp.isBlocking())
{
((AsyncEndPoint)endp).asyncDispatch();
}
}
/* ------------------------------------------------------------ */
protected void scheduleTimeout()
{
EndPoint endp=_connection.getEndPoint();
if (_timeoutMs>0)
{
if (endp.isBlocking())
{
synchronized(this)
{
_expireAt = System.currentTimeMillis()+_timeoutMs;
long wait=_timeoutMs;
while (_expireAt>0 && wait>0 && _connection.getServer().isRunning())
{
try
{
this.wait(wait);
}
catch (InterruptedException e)
{
LOG.ignore(e);
}
wait=_expireAt-System.currentTimeMillis();
}
if (_expireAt>0 && wait<=0 && _connection.getServer().isRunning())
{
expired();
}
}
}
else
{
((AsyncEndPoint)endp).scheduleTimeout(_event,_timeoutMs);
}
}
}
/* ------------------------------------------------------------ */
protected void cancelTimeout()
{
EndPoint endp=_connection.getEndPoint();
if (endp.isBlocking())
{
synchronized(this)
{
_expireAt=0;
this.notifyAll();
}
}
else
{
final AsyncEventState event=_event;
if (event!=null)
{
((AsyncEndPoint)endp).cancelTimeout(event);
}
}
}
/* ------------------------------------------------------------ */
public boolean isCompleting()
{
synchronized (this)
{
return _state==__COMPLETING;
}
}
/* ------------------------------------------------------------ */
boolean isUncompleted()
{
synchronized (this)
{
return _state==__UNCOMPLETED;
}
}
/* ------------------------------------------------------------ */
public boolean isComplete()
{
synchronized (this)
{
return _state==__COMPLETED;
}
}
/* ------------------------------------------------------------ */
public boolean isAsyncStarted()
{
synchronized (this)
{
switch(_state)
{
case __ASYNCSTARTED:
case __REDISPATCHING:
case __REDISPATCH:
case __ASYNCWAIT:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
public boolean isAsync()
{
synchronized (this)
{
switch(_state)
{
case __IDLE:
case __DISPATCHED:
case __UNCOMPLETED:
case __COMPLETED:
return false;
default:
return true;
}
}
}
/* ------------------------------------------------------------ */
public void dispatch(ServletContext context, String path)
{
_event._dispatchContext=context;
_event._pathInContext=path;
dispatch();
}
/* ------------------------------------------------------------ */
public void dispatch(String path)
{
_event._pathInContext=path;
dispatch();
}
/* ------------------------------------------------------------ */
public Request getBaseRequest()
{
return _connection.getRequest();
}
/* ------------------------------------------------------------ */
public ServletRequest getRequest()
{
if (_event!=null)
return _event.getRequest();
return _connection.getRequest();
}
/* ------------------------------------------------------------ */
public ServletResponse getResponse()
{
if (_event!=null)
return _event.getResponse();
return _connection.getResponse();
}
/* ------------------------------------------------------------ */
public void start(final Runnable run)
{
final AsyncEventState event=_event;
if (event!=null)
{
_connection.getServer().getThreadPool().dispatch(new Runnable()
{
public void run()
{
((Context)event.getServletContext()).getContextHandler().handle(run);
}
});
}
}
/* ------------------------------------------------------------ */
public boolean hasOriginalRequestAndResponse()
{
synchronized (this)
{
return (_event!=null && _event.getRequest()==_connection._request && _event.getResponse()==_connection._response);
}
}
/* ------------------------------------------------------------ */
public ContextHandler getContextHandler()
{
final AsyncEventState event=_event;
if (event!=null)
return ((Context)event.getServletContext()).getContextHandler();
return null;
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#isResumed()
*/
public boolean isResumed()
{
synchronized (this)
{
return _resumed;
}
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#isExpired()
*/
public boolean isExpired()
{
synchronized (this)
{
return _expired;
}
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#resume()
*/
public void resume()
{
dispatch();
}
/* ------------------------------------------------------------ */
protected void suspend(final ServletContext context,
final ServletRequest request,
final ServletResponse response)
{
synchronized (this)
{
doSuspend(context,request,response);
if (request instanceof HttpServletRequest)
{
_event._pathInContext = URIUtil.addPaths(((HttpServletRequest)request).getServletPath(),((HttpServletRequest)request).getPathInfo());
}
}
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#suspend()
*/
public void suspend(ServletResponse response)
{
_responseWrapped=!(response instanceof Response);
doSuspend(_connection.getRequest().getServletContext(),_connection.getRequest(),response);
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#suspend()
*/
public void suspend()
{
_responseWrapped=false;
doSuspend(_connection.getRequest().getServletContext(),_connection.getRequest(),_connection.getResponse());
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#getServletResponse()
*/
public ServletResponse getServletResponse()
{
if (_responseWrapped && _event!=null && _event.getResponse()!=null)
return _event.getResponse();
return _connection.getResponse();
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#getAttribute(java.lang.String)
*/
public Object getAttribute(String name)
{
return _connection.getRequest().getAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#removeAttribute(java.lang.String)
*/
public void removeAttribute(String name)
{
_connection.getRequest().removeAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#setAttribute(java.lang.String, java.lang.Object)
*/
public void setAttribute(String name, Object attribute)
{
_connection.getRequest().setAttribute(name,attribute);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#undispatch()
*/
public void undispatch()
{
if (isSuspended())
{
if (LOG.isDebugEnabled())
throw new ContinuationThrowable();
else
throw __exception;
}
throw new IllegalStateException("!suspended");
}
/* ------------------------------------------------------------ */
/* ------------------------------------------------------------ */
public class AsyncEventState extends Timeout.Task implements Runnable
{
private final ServletContext _suspendedContext;
private final ServletRequest _request;
private final ServletResponse _response;
private ServletContext _dispatchContext;
private String _pathInContext;
public AsyncEventState(ServletContext context, ServletRequest request, ServletResponse response)
{
_suspendedContext=context;
_request=request;
_response=response;
// Get the base request So we can remember the initial paths
Request r=_connection.getRequest();
// If we haven't been async dispatched before
if (r.getAttribute(AsyncContext.ASYNC_REQUEST_URI)==null)
{
// We are setting these attributes during startAsync, when the spec implies that
// they are only available after a call to AsyncContext.dispatch(...);
// have we been forwarded before?
String uri=(String)r.getAttribute(Dispatcher.FORWARD_REQUEST_URI);
if (uri!=null)
{
r.setAttribute(AsyncContext.ASYNC_REQUEST_URI,uri);
r.setAttribute(AsyncContext.ASYNC_CONTEXT_PATH,r.getAttribute(Dispatcher.FORWARD_CONTEXT_PATH));
r.setAttribute(AsyncContext.ASYNC_SERVLET_PATH,r.getAttribute(Dispatcher.FORWARD_SERVLET_PATH));
r.setAttribute(AsyncContext.ASYNC_PATH_INFO,r.getAttribute(Dispatcher.FORWARD_PATH_INFO));
r.setAttribute(AsyncContext.ASYNC_QUERY_STRING,r.getAttribute(Dispatcher.FORWARD_QUERY_STRING));
}
else
{
r.setAttribute(AsyncContext.ASYNC_REQUEST_URI,r.getRequestURI());
r.setAttribute(AsyncContext.ASYNC_CONTEXT_PATH,r.getContextPath());
r.setAttribute(AsyncContext.ASYNC_SERVLET_PATH,r.getServletPath());
r.setAttribute(AsyncContext.ASYNC_PATH_INFO,r.getPathInfo());
r.setAttribute(AsyncContext.ASYNC_QUERY_STRING,r.getQueryString());
}
}
}
public ServletContext getSuspendedContext()
{
return _suspendedContext;
}
public ServletContext getDispatchContext()
{
return _dispatchContext;
}
public ServletContext getServletContext()
{
return _dispatchContext==null?_suspendedContext:_dispatchContext;
}
public ServletRequest getRequest()
{
return _request;
}
public ServletResponse getResponse()
{
return _response;
}
/* ------------------------------------------------------------ */
/**
* @return The path in the context
*/
public String getPath()
{
return _pathInContext;
}
@Override
public void expired()
{
AsyncContinuation.this.expired();
}
public void run()
{
AsyncContinuation.this.expired();
}
}
}