org.mortbay.cometd
Class AbstractCometdServlet

java.lang.Object
  extended by javax.servlet.GenericServlet
      extended by javax.servlet.http.HttpServlet
          extended by org.mortbay.cometd.AbstractCometdServlet
All Implemented Interfaces:
Serializable, Servlet, ServletConfig
Direct Known Subclasses:
ContinuationCometdServlet

public abstract class AbstractCometdServlet
extends HttpServlet

Cometd Filter Servlet implementing the AbstractBayeux protocol. The Servlet can be initialized with a json file mapping channels to DataFilter definitions. The servlet init parameter "filters" should point to a webapplication resource containing a JSON array of filter definitions. For example:

  [
    { 
      "channels": "/**",
      "class"   : "org.mortbay.cometd.filter.NoMarkupFilter",
      "init"    : {}
    }
  ]
 
The following init parameters can be used to configure the servlet:
timeout
The server side poll timeout in milliseconds (default 250000). This is how long the server will hold a reconnect request before responding.
interval
The client side poll timeout in milliseconds (default 0). How long a client will wait between reconnects
maxInterval
The max client side poll timeout in milliseconds (default 30000). A client will be removed if a connection is not received in this time.
multiFrameInterval
the client side poll timeout if multiple connections are detected from the same browser (default 1500).
JSONCommented
If "true" then the server will accept JSON wrapped in a comment and will generate JSON wrapped in a comment. This is a defence against Ajax Hijacking.
alwaysResumePoll
If true, then reconnect requests will always be resumed when a message is delivered. This may be needed for some cross domain transports that need strict ordering of responses.
filters
the location of a JSON file describing DataFilter instances to be installed
requestAvailable
If true, the current request is made available via the AbstractBayeux.getCurrentRequest() method
loglevel
0=none, 1=info, 2=debug
directDeliver
true if published messages are delivered directly to subscribers (default). If false, a message copy is created with only supported fields

Author:
gregw, aabeling: added JSONP transport
See Also:
AbstractBayeux}, ChannelId}, Serialized Form

Field Summary
protected  AbstractBayeux _bayeux
           
static String BROWSER_ID
           
static String CLIENT_ATTR
           
static String HTTP_CLIENT_ID
           
static String MESSAGE_PARAM
           
static String TRANSPORT_ATTR
           
static String TUNNEL_INIT_PARAM
           
 
Constructor Summary
AbstractCometdServlet()
           
 
Method Summary
protected  String browserId(HttpServletRequest request)
           
 AbstractBayeux getBayeux()
           
protected  dojox.cometd.Message[] getMessages(HttpServletRequest request)
           
 void init()
           
protected abstract  AbstractBayeux newBayeux()
           
protected  String newBrowserId(HttpServletRequest request, HttpServletResponse response)
           
protected  void service(HttpServletRequest req, HttpServletResponse resp)
           
 
Methods inherited from class javax.servlet.http.HttpServlet
doDelete, doGet, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service
 
Methods inherited from class javax.servlet.GenericServlet
destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

CLIENT_ATTR

public static final String CLIENT_ATTR
See Also:
Constant Field Values

TRANSPORT_ATTR

public static final String TRANSPORT_ATTR
See Also:
Constant Field Values

MESSAGE_PARAM

public static final String MESSAGE_PARAM
See Also:
Constant Field Values

TUNNEL_INIT_PARAM

public static final String TUNNEL_INIT_PARAM
See Also:
Constant Field Values

HTTP_CLIENT_ID

public static final String HTTP_CLIENT_ID
See Also:
Constant Field Values

BROWSER_ID

public static final String BROWSER_ID
See Also:
Constant Field Values

_bayeux

protected AbstractBayeux _bayeux
Constructor Detail

AbstractCometdServlet

public AbstractCometdServlet()
Method Detail

getBayeux

public AbstractBayeux getBayeux()

newBayeux

protected abstract AbstractBayeux newBayeux()

init

public void init()
          throws ServletException
Overrides:
init in class GenericServlet
Throws:
ServletException

service

protected void service(HttpServletRequest req,
                       HttpServletResponse resp)
                throws ServletException,
                       IOException
Overrides:
service in class HttpServlet
Throws:
ServletException
IOException

browserId

protected String browserId(HttpServletRequest request)

newBrowserId

protected String newBrowserId(HttpServletRequest request,
                              HttpServletResponse response)

getMessages

protected dojox.cometd.Message[] getMessages(HttpServletRequest request)
                                      throws IOException
Throws:
IOException


Copyright © 2008 Mort Bay Consulting. All Rights Reserved.