Unfriendly error message for configuration errors in JMeter

**Sai Zhang** ([Bug 56862](https://bz.apache.org/bugzilla//show_bug.cgi?id=56862&redirect=false)):
Dear JMeter developers,

The error messages dumped by JMeter (caused by configuration errors) are rather confusing in some cases. I strongly suggest to improve these error messages. Doing so would dramatically improve JMeter's usability.

Here are two reproducible examples:

1.

//if I set the following invalid option value in jmeter.properties
jmeterengine.threadstop.wait=-1000

Jmeter simply dumps the error message:

Uncaught Exception java.lang.IllegalArgumentException: timeout value is negative. See log file for details.

(the above error message is really not informative. there is not much connection between "timeout" and the wrong option value "threadstop.wait". Further, the log file does not say anything too. This costs me extra debugging time for this simple mistakes. I would suggest to add show the *configuration name* or the *configuration value* in the error message)

2.

Similar to the above error, if I set:

oro.patterncache.size=-1001

Jmeter dumps the error message:

Uncaught Exception java.lang.ExceptionInInitializerError. See log file for details.

This is even less useful, and the log file does not show anything useful either.

I would suggest to check the configuration option value when JMeter starts, and improve the corresponding error message (or logs).

Thanks

-Sai

OS: All