Q:

Grails from command line gets number format exceptions in threads and cannot recover

When running Grails in the Windows Command Prompt in development mode, after invoking run-app, I often get a few NumberFormatExceptions thrown for Threads after making changes to code and saving. This particularly happens when changing conf files or if there is a compile error in my code. 
The only way to recover that I've found is to close the command prompt window, open a new one, start Grails again, then issue a stop-app and run-app.
Is there another way?
Text from the command window is below:
| Compiling 1 source files.

grails>

Exception: java.lang.NumberFormatException thrown from the UncaughtExceptionHandler in thread "Thread-14"

Exception: java.lang.NumberFormatException thrown from the UncaughtExceptionHandler in thread "Thread-24"

A:

@BurtBeckwith found the solution to this. It appears to be related to running grails on a Windows development environment.  Raised in JIRA:  http://jira.grails.org/browse/GRAILS-9356.  The issue occurs when you start a DOS command window, type "grails" then within grails, do run-app.  The solution is to start the DOS command window and type "grails run-app" together.  It runs much more stable like this. Then, closing the command window kills the java.exe task and no need to do a stop-app. 

