Error while launching of the application thru java web start

Question

I have java webstart 1.2. While opening one of the application, its showing me following error message,
"javaws.exe has generated error and will be closed by Windows. You will need to restart the program. An error log is being created."
After that application works fine(It does not close the application) and no log file is generated.
Can any one tell me what is the cause of this problem.
Regards,
Pravanjana

Answer 1

You shouldn't give up without studying the source of JMF.
JMFSecurityManager blocks opening the webcam when it recognizes that the application is executed as an applet. JMF - in fact JMFSecurityManager - cannot distinguish between an applet and a java webstart application because it only evaluates System.getSecurityManager().
If the application is deployed via webstart the System.SecutityManager is NOT null and so JMFSecurityManager makes problems.
So the easiest solution of this problem is to call System.setSecurityManager(null) before any static function of JMF is executed or any class of the Framework is instanciated - e.g in the main-function. Java webstart allows to execute the command if the .jnlp-file requests all-permissions.
Another possibility is to read the properties. Therefore jmutil.dll has to be deployed and in C:\WINDOWS\java\.jmfdir the first line must contain the path of jmf.properties. This should be an alternative but I haven't checked if it works.