Absent Member.
Absent Member.

GWT Error during recording when "Enable data format extension" is turned on



I've been running into the following error when recording a web application using GWT 2.4 and JRE6:


!!!!!! Web Error: ERROR - DFE !!!!!!
Extension: GWT - ERROR [GWT_DFE] - error in perProcessInitInternal:com.hp.dfe.exceptions.GWTClassesNotFoundException: GWT classes not found, please add GWT jar or classes to the classpath
at com.hp.dfe.GWT_DFE_LAUNCHER.extendClassLoader(GWT_DFE_LAUNCHER.java:167)
at com.hp.dfe.GWT_DFE_LAUNCHER.perProcessInitInternal(GWT_DFE_LAUNCHER.java:117)
at com.hp.dfe.GWT_DFE_LAUNCHER.perProcessInit(GWT_DFE_LAUNCHER.java:100)
Caused by: java.lang.NoClassDefFoundError: com/google/gwt/user/client/rpc/IncompatibleRemoteServiceException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getDeclaredMethods(Class.java:1791)
... 3 more
Caused by: java.lang.ClassNotFoundException: com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at com.hp.dfe.ReversedClassLoader.loadClass(ReversedClassLoader.java:32)
at com.hp.dfe.ReversedClassLoader.loadClass(ReversedClassLoader.java:11)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
... 7 more


I'm running vugen 11.50.2552.0.  I did all the necessary setup for using data format extension:

- Add Chain Configuration with the web application's war file

- Select "Enable data format extension" in Code generation, and added chain to both Body and Headers under the Chain Assignment

- selected x-gwt-permutation in HTTP PRoperties/Advanced.


Any help will be greatly appreciated.




- Thomas To -

5 Replies
Absent Member.
Absent Member.

The class paths for the web chain is not the path to the war file.

Please include the paths below:

1. the path to the .gwt.rpc files. e.g <webServerApplicationsPath>\ApplicationName\<GWTApplicationName

2. the file to the jar files.  e.g. <webServerApplicationsPath>\ApplicationName\WEB-INF\lib\<anyJarFileName>.jar 

3. the path to the classes. e.g. <webServerApplicationsPath>\ApplicationName\WEB-INF\classes

New Member.

In fact, using the WAR file from the application should save you the need to configure .JARs, .CLASS folder and .GWT.RPC folder.
However, you must make sure that WAR file you are using is up to date with the one used in the recorded application. If the application has been updated by R&D, make sure you get the latest WAR file.


The caught exception, "IncompatibleRemoteServiceException", can indicate that a newer version of the WAR file was deployed to the server, and that this version includes new .gwt.rpc files that are missing in the WAR file used for code generation or for replay.


Another common cause for this issue is third party classes used in the application. Search the server for .WAR, .JAR, .CLASS and .GWT.RPC files. If such files are found, copy them to a local folder and include them in the GWT DFE chain configuration.

Specifically, check if third party tools are used for logging or xml serialization (namely Log4J, Xstreamer and XPP).


If possible, email me the full exception stack trace printed to the log.


I suggest to open a support request and to escalate it to me. You can mention me by name, hopefully it will help the request reach me quicker.

Please include the recorded script and the used WAR file in the support request.


Thanks and regards,

Oded Keret
Absent Member.
Absent Member.

Thank for the suggestion, Oded.  I will check with Dev for any 3rd party related files and the up to date WAR file.  Will get back soon....


btw, I have the entire WAR file copied to the vugen host and just pointed the chain to this war file.

Absent Member.. Absent Member..
Absent Member..



I have the same problem when running in VUGen 12.5 a script recorded in 11.52 (DFE GWT).

Have you fixed this issue and how?

Many thanks.

Honored Contributor.
Honored Contributor.



these error messages indicate that the WAR file you are using is probably out dated...


please verify that all the files that oded mention in the previos comment exist.

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