RPC error - garbled text as the response.

[cij100]

Hi,

I have a gwt based application,that uses RPC calls to communicate with
the server. Normally this works fine, however occasionally the
response fails and I'm unsure what is causing it. Using firebug, I can
see the response is garbled text instead of the OK message. An example
of the response is below:

f8
� ��������PKk�0�/9�`�G �>�0rXYz ] ����Q�f�~N�8
V���IH� �77��� k�" ~�� I4�*3�� �,��A1�e_<��-� ��*�vچ�xi�th�r +�'8F �C
$�+��q��<to ]�OP ����U��ڠ�2ş,
>�xJ� �'������F�˛7q�O��6�̵�J �h/�����㍕�
ռ������j��y Vb���O�^g��"� ��� + -5��� ��
0

The server logs seem to show the server impl processing was completed
sucessfully, but the localhost log shows the following stack trace:

12-Mar-2009 08:52:13 org.apache.catalina.core.StandardWrapperValve
invoke
SEVERE: Servlet.service() for servlet default threw exception
java.lang.IllegalStateException
at org.apache.catalina.connector.ResponseFacade.sendError
(ResponseFacade.java:404)
at org.apache.catalina.servlets.DefaultServlet.serveResource
(DefaultServlet.java:698)
at org.apache.catalina.servlets.DefaultServlet.doGet
(DefaultServlet.java:354)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter
(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter
(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke
(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke
(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke
(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke
(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke
(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service
(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11AprProcessor.process
(Http11AprProcessor.java:833)
at org.apache.coyote.http11.Http11AprProtocol
$Http11ConnectionHandler.process(Http11AprProtocol.java:639)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:
1285)
at java.lang.Thread.run(Thread.java:619)


At present I am still using gwt1.4, the inention is to upgrade to 1.5
shortly, and it's running against a tomcat 6 server.

Is there anything obvious that I need to do to avoid these sorts of
error, or methods to debug what has gone wrong between me completing
the impl code processing and recieving the response on the client?

Thanks.

[Magius]

I remenber to have read that GWT-RPC zips the data sent in some cases.
And your message has a "PK" mark, the same that for ZIP files.
If this is true the RPC message could be ok.

I cannot help wtith the rest. In the exception log there isn't any gwt
classes...

By the way, I migrated from GWT 1.4 to 1.5 with almost no changes in
the code.
And GWT 1.5 compiles faster and using a lot of less memory.

I hope it helps a bit.

[gregor]

(DefaultServlet.java:698)
at org.apache.catalina.servlets.DefaultServlet.doGet
(DefaultServlet.java:354)

That doesn't look right. Are you sure this stack trace was caused by
your RPC service call? If it was you need to figure out how come a
doGet(..) is being called. GWT RPC servlets use POST AFAIK.