Internal Error occurs after redeployment

General
1

I get an ‘internal error’ (see log below) involving the CommunicationManager class.
This occurs after I redeploy my application which was working ok before.
I suppose I changed something in a wrong way, but I can’t guess what ?

ps : I use JBoss 4.0.5, and the error persists, even after a full server restart …

2009-09-23 10:34:50,087 ERROR [STDERR]
java.lang.NullPointerException
2009-09-23 10:34:50,087 ERROR [STDERR]
at com.vaadin.terminal.gwt.server.CommunicationManager.paintAfterVariablechanges(CommunicationManager.java:364)
2009-09-23 10:34:50,087 ERROR [STDERR]
at com.vaadin.terminal.gwt.server.CommunicationManager.handleUidlRequest(CommunicationManager.java:314)
2009-09-23 10:34:50,087 ERROR [STDERR]
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:425)
2009-09-23 10:34:50,087 ERROR [STDERR]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
2009-09-23 10:34:50,087 ERROR [STDERR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:175)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:74)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.jboss.web.tomcat.tc5.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:156)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
2009-09-23 10:34:50,103 ERROR [STDERR]
at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
2009-09-23 10:34:50,103 ERROR [STDERR]
at java.lang.Thread.run(Thread.java:595)

2

Either there is some additional stack trace which you have left out or something is eating the real cause. I would recommend you run JBoss in debug mode and set a NullPointerException break point to see where the error is actually coming from. You don’t mention which Vaadin version you are using and in my current copy CommunicationManager:364 is

JsonPaintTarget paintTarget = new JsonPaintTarget(this, outWriter, which makes no sense for a NPE.

3

So I did what you suggest : I set a nullpointer exception break point, but it gives me the same answer :

“CommunicationManager.paintAfterVariableChanges Line 364…”

The stack trace I sent is all I could find in my server log (nothing before, nothing after).

I use vaadin-6.1.0.jar with a Jboss 4.0.5, running with a JDK 1.5 in an eclipse J2EE 3.4.2

By the way I also compile my sources with JDK 1.5, could it be the reason ?

4

Sorry, it seems the line numbers in my version was way off, the correct line 364 is

        if (!window.getName().equals(closingWindowName)) {

So my guess would be that you create a window with null name, something you can confirm when the debugger breaks on the NPE. It should not be possible for “window” to be null at this point.

5

Problem partially solved !

The only window I create is the main window, so I set a name on it (window.setName()), and the error disappeared !

Now, I get a blank page, but with the debug window (?debug) I can see that I have layout pb.
Running the ‘Analyze layout’ it gives me the following messages :

[font=Courier New]
Layouts analyzed on server, total top level problems: 2
Root problems

(null) id: PID0
Height problem: A component with relative height needs a parent with defined height.
Emphasis component in UI

(null) id: PID1
Height problem: Component with relative height inside a VerticalLayout with no height defined.
Emphasis component in UI
Expand this node to show problems that may be dependent on this problem.

(null) id: PID2
Height problem: A component with relative height needs a parent with defined height.
Emphasis component in UI
Expand this node to show problems that may be dependent on this problem.

(null) id: PID3
Height problem: Component with relative height inside a VerticalLayout with no height defined.
Emphasis component in UI

Processing time was 78ms for 931 characters of JSON
Referenced paintables: 0
[/font]

Any way, I know where to search now, and I suppose these problems were the cause of the other…

Thanks for your help