org.eclipse.jetty.server.HttpChannelState Maven / Gradle / Ivy
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//
// ========================================================================
// Copyright (c) 1995-2012 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 java.util.concurrent.TimeUnit;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
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.Scheduler;
/* ------------------------------------------------------------ */
/** Implementation of AsyncContext interface that holds the state of request-response cycle.
*
*
* STATE ACTION handling() startAsync() unhandle() dispatch() complete() completed() IDLE: DISPATCHED COMPLETECALLED?? DISPATCHED: ASYNCSTARTED COMPLETING ASYNCSTARTED: ASYNCWAIT REDISPATCHING COMPLETECALLED REDISPATCHING: REDISPATCHED ASYNCWAIT: REDISPATCH COMPLETECALLED REDISPATCH: REDISPATCHED REDISPATCHED: ASYNCSTARTED COMPLETING COMPLETECALLED: COMPLETING COMPLETING COMPLETING: COMPLETING COMPLETED COMPLETED:
*
*/
public class HttpChannelState implements AsyncContext
{
private static final Logger LOG = Log.getLogger(HttpChannelState.class);
private final static long DEFAULT_TIMEOUT=30000L;
public enum State
{
IDLE, // Idle request
DISPATCHED, // Request dispatched to filter/servlet
ASYNCSTARTED, // Suspend called, but not yet returned to container
REDISPATCHING, // resumed while dispatched
ASYNCWAIT, // Suspended and parked
REDISPATCH, // Has been scheduled
REDISPATCHED, // Request redispatched to filter/servlet
COMPLETECALLED,// complete called
COMPLETING, // Request is completable
COMPLETED // Request is complete
}
/* ------------------------------------------------------------ */
private final HttpChannel _channel;
private List _lastAsyncListeners;
private List _asyncListeners;
/* ------------------------------------------------------------ */
private State _state;
private boolean _initial;
private boolean _dispatched;
private boolean _expired;
private volatile boolean _responseWrapped;
private long _timeoutMs=DEFAULT_TIMEOUT;
private AsyncEventState _event;
/* ------------------------------------------------------------ */
protected HttpChannelState(HttpChannel channel)
{
_channel=channel;
_state=State.IDLE;
_initial=true;
}
/* ------------------------------------------------------------ */
public State getState()
{
synchronized(this)
{
return _state;
}
}
/* ------------------------------------------------------------ */
@Override
public void addListener(AsyncListener listener)
{
synchronized(this)
{
if (_asyncListeners==null)
_asyncListeners=new ArrayList<>();
_asyncListeners.add(listener);
}
}
/* ------------------------------------------------------------ */
@Override
public void addListener(AsyncListener listener,ServletRequest request, ServletResponse response)
{
synchronized(this)
{
if (_asyncListeners==null)
_asyncListeners=new ArrayList<>();
_asyncListeners.add(listener);
}
}
/* ------------------------------------------------------------ */
@Override
public void setTimeout(long ms)
{
synchronized(this)
{
_timeoutMs=ms;
}
}
/* ------------------------------------------------------------ */
@Override
public long getTimeout()
{
synchronized(this)
{
return _timeoutMs;
}
}
/* ------------------------------------------------------------ */
public AsyncEventState getAsyncEventState()
{
synchronized(this)
{
return _event;
}
}
/* ------------------------------------------------------------ */
@Override
public String toString()
{
synchronized (this)
{
return super.toString()+"@"+getStatusString();
}
}
/* ------------------------------------------------------------ */
public String getStatusString()
{
synchronized (this)
{
return _state+
(_initial?",initial":"")+
(_dispatched?",resumed":"")+
(_expired?",expired":"");
}
}
/* ------------------------------------------------------------ */
/**
* @return true if the handling of the request should proceed
*/
protected boolean handling()
{
synchronized (this)
{
switch(_state)
{
case IDLE:
_initial=true;
_state=State.DISPATCHED;
if (_lastAsyncListeners!=null)
_lastAsyncListeners.clear();
if (_asyncListeners!=null)
_asyncListeners.clear();
else
{
_asyncListeners=_lastAsyncListeners;
_lastAsyncListeners=null;
}
break;
case COMPLETECALLED:
_state=State.COMPLETING;
return false;
case ASYNCWAIT:
case COMPLETING:
case COMPLETED:
return false;
case REDISPATCH:
_state=State.REDISPATCHED;
break;
default:
throw new IllegalStateException(this.getStatusString());
}
_responseWrapped=false;
return true;
}
}
/* ------------------------------------------------------------ */
public void startAsync()
{
synchronized (this)
{
switch(_state)
{
case DISPATCHED:
case REDISPATCHED:
_dispatched=false;
_expired=false;
_responseWrapped=false;
_event=new AsyncEventState(_channel.getRequest().getServletContext(),_channel.getRequest(),_channel.getResponse());
_state=State.ASYNCSTARTED;
List listeners=_lastAsyncListeners;
_lastAsyncListeners=_asyncListeners;
_asyncListeners=listeners;
if (_asyncListeners!=null)
_asyncListeners.clear();
break;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (_lastAsyncListeners!=null)
{
for (AsyncListener listener : _lastAsyncListeners)
{
try
{
listener.onStartAsync(_event);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#suspend(long)
*/
public void startAsync(final ServletContext context,final ServletRequest request,final ServletResponse response)
{
synchronized (this)
{
switch(_state)
{
case DISPATCHED:
case REDISPATCHED:
_dispatched=false;
_expired=false;
_responseWrapped=response!=_channel.getResponse();
_event=new AsyncEventState(context,request,response);
_event._pathInContext = (request instanceof HttpServletRequest)?URIUtil.addPaths(((HttpServletRequest)request).getServletPath(),((HttpServletRequest)request).getPathInfo()):null;
_state=State.ASYNCSTARTED;
List listeners=_lastAsyncListeners;
_lastAsyncListeners=_asyncListeners;
_asyncListeners=listeners;
if (_asyncListeners!=null)
_asyncListeners.clear();
break;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (_lastAsyncListeners!=null)
{
for (AsyncListener listener : _lastAsyncListeners)
{
try
{
listener.onStartAsync(_event);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
}
/* ------------------------------------------------------------ */
protected void error(Throwable th)
{
synchronized (this)
{
if (_event!=null)
_event._cause=th;
}
}
/* ------------------------------------------------------------ */
/**
* 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)
{
switch(_state)
{
case REDISPATCHED:
case DISPATCHED:
_state=State.COMPLETING;
return true;
case IDLE:
throw new IllegalStateException(this.getStatusString());
case ASYNCSTARTED:
_initial=false;
_state=State.ASYNCWAIT;
scheduleTimeout();
if (_state==State.ASYNCWAIT)
return true;
else if (_state==State.COMPLETECALLED)
{
_state=State.COMPLETING;
return true;
}
_initial=false;
_state=State.REDISPATCHED;
return false;
case REDISPATCHING:
_initial=false;
_state=State.REDISPATCHED;
return false;
case COMPLETECALLED:
_initial=false;
_state=State.COMPLETING;
return true;
default:
throw new IllegalStateException(this.getStatusString());
}
}
}
/* ------------------------------------------------------------ */
@Override
public void dispatch()
{
boolean dispatch=false;
synchronized (this)
{
switch(_state)
{
case ASYNCSTARTED:
_state=State.REDISPATCHING;
_dispatched=true;
return;
case ASYNCWAIT:
dispatch=!_expired;
_state=State.REDISPATCH;
_dispatched=true;
break;
case REDISPATCH:
return;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (dispatch)
{
cancelTimeout();
scheduleDispatch();
}
}
/* ------------------------------------------------------------ */
/**
* @see Continuation#isDispatched()
*/
public boolean isDispatched()
{
synchronized (this)
{
return _dispatched;
}
}
/* ------------------------------------------------------------ */
protected void expired()
{
final List aListeners;
synchronized (this)
{
switch(_state)
{
case ASYNCSTARTED:
case ASYNCWAIT:
aListeners=_asyncListeners;
break;
default:
aListeners=null;
return;
}
_expired=true;
}
if (aListeners!=null)
{
for (AsyncListener listener : aListeners)
{
try
{
listener.onTimeout(_event);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
synchronized (this)
{
switch(_state)
{
case ASYNCSTARTED:
case ASYNCWAIT:
complete();
}
}
scheduleDispatch();
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#complete()
*/
@Override
public void complete()
{
// just like resume, except don't set _dispatched=true;
boolean dispatch=false;
synchronized (this)
{
switch(_state)
{
case DISPATCHED:
case REDISPATCHED:
throw new IllegalStateException(this.getStatusString());
case IDLE:
case ASYNCSTARTED:
_state=State.COMPLETECALLED;
return;
case ASYNCWAIT:
_state=State.COMPLETECALLED;
dispatch=!_expired;
break;
default:
throw new IllegalStateException(this.getStatusString());
}
}
if (dispatch)
{
cancelTimeout();
scheduleDispatch();
}
}
/* ------------------------------------------------------------ */
@Override
public T createListener(Class clazz) throws ServletException
{
try
{
// TODO inject
return clazz.newInstance();
}
catch(Exception e)
{
throw new ServletException(e);
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#complete()
*/
protected void completed()
{
final List aListeners;
synchronized (this)
{
switch(_state)
{
case COMPLETING:
_state=State.COMPLETED;
aListeners=_asyncListeners;
break;
default:
aListeners=null;
throw new IllegalStateException(this.getStatusString());
}
}
if (aListeners!=null)
{
for (AsyncListener listener : aListeners)
{
try
{
if (_event!=null && _event._cause!=null)
{
_event.getSuppliedRequest().setAttribute(RequestDispatcher.ERROR_EXCEPTION,_event._cause);
_event.getSuppliedRequest().setAttribute(RequestDispatcher.ERROR_MESSAGE,_event._cause.getMessage());
listener.onError(_event);
}
else
listener.onComplete(_event);
}
catch(Exception e)
{
LOG.warn(e);
}
}
}
}
/* ------------------------------------------------------------ */
protected void recycle()
{
synchronized (this)
{
switch(_state)
{
case DISPATCHED:
case REDISPATCHED:
throw new IllegalStateException(getStatusString());
default:
_state=State.IDLE;
}
_initial = true;
_dispatched=false;
_expired=false;
_responseWrapped=false;
cancelTimeout();
_timeoutMs=DEFAULT_TIMEOUT;
_event=null;
}
}
/* ------------------------------------------------------------ */
public void cancel()
{
synchronized (this)
{
cancelTimeout();
}
}
/* ------------------------------------------------------------ */
protected void scheduleDispatch()
{
_channel.execute(_channel);
}
/* ------------------------------------------------------------ */
protected void scheduleTimeout()
{
Scheduler scheduler = _channel.getScheduler();
if (scheduler!=null && _timeoutMs>0)
_event._timeout=scheduler.schedule(new AsyncTimeout(),_timeoutMs,TimeUnit.MILLISECONDS);
}
/* ------------------------------------------------------------ */
protected void cancelTimeout()
{
AsyncEventState event=_event;
if (event!=null)
{
Scheduler.Task task=event._timeout;
if (task!=null)
task.cancel();
}
}
/* ------------------------------------------------------------ */
/* (non-Javadoc)
* @see javax.servlet.ServletRequest#isInitial()
*/
public boolean isInitial()
{
synchronized(this)
{
return _initial;
}
}
/* ------------------------------------------------------------ */
public boolean isSuspended()
{
synchronized(this)
{
switch(_state)
{
case ASYNCSTARTED:
case REDISPATCHING:
case COMPLETECALLED:
case ASYNCWAIT:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
boolean isCompleting()
{
synchronized (this)
{
return _state==State.COMPLETING;
}
}
/* ------------------------------------------------------------ */
public boolean isAsync()
{
synchronized (this)
{
switch(_state)
{
case ASYNCSTARTED:
case REDISPATCHING:
case ASYNCWAIT:
case REDISPATCHED:
case REDISPATCH:
case COMPLETECALLED:
return true;
default:
return false;
}
}
}
/* ------------------------------------------------------------ */
@Override
public void dispatch(ServletContext context, String path)
{
_event._dispatchContext=context;
_event._pathInContext=path;
dispatch();
}
/* ------------------------------------------------------------ */
@Override
public void dispatch(String path)
{
_event._pathInContext=path;
dispatch();
}
/* ------------------------------------------------------------ */
public Request getBaseRequest()
{
return _channel.getRequest();
}
/* ------------------------------------------------------------ */
@Override
public ServletRequest getRequest()
{
if (_event!=null)
return _event.getSuppliedRequest();
return _channel.getRequest();
}
/* ------------------------------------------------------------ */
@Override
public ServletResponse getResponse()
{
if (_responseWrapped && _event!=null && _event.getSuppliedResponse()!=null)
return _event.getSuppliedResponse();
return _channel.getResponse();
}
/* ------------------------------------------------------------ */
@Override
public void start(final Runnable run)
{
final AsyncEventState event=_event;
if (event!=null)
{
_channel.execute(new Runnable()
{
@Override
public void run()
{
((Context)event.getServletContext()).getContextHandler().handle(run);
}
});
}
}
/* ------------------------------------------------------------ */
@Override
public boolean hasOriginalRequestAndResponse()
{
synchronized (this)
{
return (_event!=null && _event.getSuppliedRequest()==_channel.getRequest() && _event.getSuppliedResponse()==_channel.getResponse());
}
}
/* ------------------------------------------------------------ */
public ContextHandler getContextHandler()
{
final AsyncEventState event=_event;
if (event!=null)
return ((Context)event.getServletContext()).getContextHandler();
return null;
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#getServletResponse()
*/
public ServletResponse getServletResponse()
{
if (_responseWrapped && _event!=null && _event.getSuppliedResponse()!=null)
return _event.getSuppliedResponse();
return _channel.getResponse();
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#getAttribute(java.lang.String)
*/
public Object getAttribute(String name)
{
return _channel.getRequest().getAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#removeAttribute(java.lang.String)
*/
public void removeAttribute(String name)
{
_channel.getRequest().removeAttribute(name);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.continuation.Continuation#setAttribute(java.lang.String, java.lang.Object)
*/
public void setAttribute(String name, Object attribute)
{
_channel.getRequest().setAttribute(name,attribute);
}
/* ------------------------------------------------------------ */
/* ------------------------------------------------------------ */
public class AsyncTimeout implements Runnable
{
@Override
public void run()
{
HttpChannelState.this.expired();
}
}
/* ------------------------------------------------------------ */
/* ------------------------------------------------------------ */
public class AsyncEventState extends AsyncEvent
{
final private ServletContext _suspendedContext;
private String _pathInContext;
private Scheduler.Task _timeout;
private ServletContext _dispatchContext;
private Throwable _cause;
public AsyncEventState(ServletContext context, ServletRequest request, ServletResponse response)
{
super(HttpChannelState.this, request,response);
_suspendedContext=context;
// Get the base request So we can remember the initial paths
Request r=_channel.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(RequestDispatcher.FORWARD_REQUEST_URI);
if (uri!=null)
{
r.setAttribute(AsyncContext.ASYNC_REQUEST_URI,uri);
r.setAttribute(AsyncContext.ASYNC_CONTEXT_PATH,r.getAttribute(RequestDispatcher.FORWARD_CONTEXT_PATH));
r.setAttribute(AsyncContext.ASYNC_SERVLET_PATH,r.getAttribute(RequestDispatcher.FORWARD_SERVLET_PATH));
r.setAttribute(AsyncContext.ASYNC_PATH_INFO,r.getAttribute(RequestDispatcher.FORWARD_PATH_INFO));
r.setAttribute(AsyncContext.ASYNC_QUERY_STRING,r.getAttribute(RequestDispatcher.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;
}
/* ------------------------------------------------------------ */
/**
* @return The path in the context
*/
public String getPath()
{
return _pathInContext;
}
}
}