GWT Remoting Example is not working

[soshah]

OS: Linux Fedora Core 6
JVM: java version "1.5.0_11"
JBoss AS: 4.2.1.GA
Seam: 2.0.0.CR2

When trying to run the GWT/Remoting example included under examples/remoting/gwt, I am getting the following stack trace:

Note: the example is deployed using 'ant deploy' and the following URL:
http://localhost:8080/seam-gwt

11:02:10,190 INFO [Server] JBoss (MX MicroKernel) [4.2.1.GA (build: SVNTag=JBoss_4_2_1_GA date=200707131605)] Started in 28s:157ms
11:02:19,279 ERROR [[default]] Servlet.service() for servlet default threw exception
java.lang.IllegalStateException: Cannot create a session after the response has been committed
 at org.apache.catalina.connector.Request.doGetSession(Request.java:2284)
 at org.apache.catalina.connector.Request.getSession(Request.java:2066)
 at org.apache.catalina.connector.RequestFacade.getSession(RequestFacade.java:833)
 at org.jboss.seam.servlet.ServletRequestSessionMap.put(ServletRequestSessionMap.java:87)
 at org.jboss.seam.servlet.ServletRequestSessionMap.put(ServletRequestSessionMap.java:25)
 at org.jboss.seam.contexts.BasicContext.set(BasicContext.java:80)
 at org.jboss.seam.Component.newInstance(Component.java:1980)
 at org.jboss.seam.Component.getInstance(Component.java:1878)
 at org.jboss.seam.Component.getInstance(Component.java:1857)
 at org.jboss.seam.Component.getInstance(Component.java:1834)
 at org.jboss.seam.web.Session.getInstance(Session.java:122)
 at org.jboss.seam.contexts.Contexts.flushAndDestroyContexts(Contexts.java:375)
 at org.jboss.seam.contexts.Lifecycle.endRequest(Lifecycle.java:132)
 at org.jboss.seam.servlet.ContextualHttpServletRequest.run(ContextualHttpServletRequest.java:65)
 at org.jboss.seam.web.ContextFilter.doFilter(ContextFilter.java:37)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
 at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:241)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:580)
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
 at java.lang.Thread.run(Thread.java:595)

Thanks

[shane.bryzak]

This bug was just fixed recently.

[soshah]

Is the bug fix related to this report?

http://jira.jboss.com/jira/browse/JBSEAM-1102

If so, looks like the bug fix should be included under 2.0.0CR2 which is what I am using,

btw- I am using the released package from the JBoss.org site, without any code changes on my part. Just following the readme instructions and deploying the example

Do you think I should try the trunk to see if the bug fix is working there?

Thanks

[soshah]

Shane-

This may very well be a hack job based on my novice understanding of Seam contexts. But after debugging here is what I did and it seems to have fixed the remote GWT example. Like I said, I am not sure what the side effects of this change could be.

Inside class org.jboss.seam.servlet.ContextualHttpServletRequest made the following change

public void run() throws ServletException, IOException
 {
 log.debug("beginning request");
 ServletLifecycle.beginRequest(request);
 ServletContexts.instance().setRequest(request);
 restoreConversationId();
 Manager.instance().restoreConversation();
 ServletLifecycle.resumeConversation(request);
 handleConversationPropagation();
 try
 {
 //This code was added, because apparently it kept throwing
 //IllegalStateException if the response has been committed
 if(request.getSession(false) == null)
 {
 request.getSession(true);
 }

 process();
 //TODO: conversation timeout
 Manager.instance().endRequest( new ServletRequestSessionMap(request) );
 ServletLifecycle.endRequest(request);
 }
 catch (IOException ioe)
 {
 Lifecycle.endRequest();
 log.error("ended request due to exception", ioe);
 throw ioe;
 }
 catch (ServletException se)
 {
 Lifecycle.endRequest();
 log.error("ended request due to exception", se);
 throw se;
 }
 catch (Exception e)
 {
 Lifecycle.endRequest();
 log.error("ended request due to exception", e);
 throw new ServletException(e);
 }
 finally
 {
 log.debug("ended request");
 }
 }

and inside the examples/remoting/gwt/resources/WEB-INF/web.xml I had to modify the filter mapping as follows:

<filter-mapping>
 <filter-name>Context Filter</filter-name>
 <url-pattern>*.html</url-pattern>
 <exclude-pattern>/seam/resource/*</exclude-pattern>
 </filter-mapping>

Thanks

[shane.bryzak]

I've moved this change from GWTService to ContextualHttpRequest, as we discussed Sohil.