Recently we had a strange problem that defied all normal problem determination and debugging. We just didn’t understand how the code could be doing what it was doing (loading a page of mixed languages). That’s when we remembered the really cool Websphere tracing *built in* to the product. What WAS tracing allows you to do is follow the code path of selected classes as they execute in real time. Any class that is enabled for tracing with the java.util.logging.* classes is fair game.
Once configured and enabled trace information is output to a trace.log file. Here’s a screen snapshot of where to go to in your WAS admin console to enable tracing:
Here’s a shot of some of the classes we were tracing:
So what happened? We discovered that the problem wasn’t in the code at all but in the way we had configured our property files. Simple, easy fix that we would still be scratching our heads over if we hadn’t used WAS tracing.