Use Log Files To Isolate Problems
Another effective techniqueprobably the simplest of allis to leverage log files as a means of capturing bugs and debugging. Often, when a problem happens behind the scenes of an application, you don't see the problem on the user interface. For example, most Java exceptions don't appear onscreen. To see those errors, you need to view the source code, the log files, or the Java console. If developers give testers access to the execution log files for the application, the testers can use scripts to parse through the log files, looking for abnormalities and exceptions. For example, as a regular part of script execution on web applications, I parse the source code and logs while the script is running. Once developers know that the testing scripts are looking for this sort of information, the developers may be more willing to take the time to output results in a common format for testers to parse.
Building testability into the application is a partnership between testers and developers. Most developers want to help in any way they can, assuming that they're given time to do so. It's up to testers to let developers know what they need. When I'm testing, and I find a new problem in a log, I ask around to see whether anyone else knows of similar problems. Often, someone else will make a suggestion and then even help me to update the log parser to look for that related error. After a short time with this sort of collaboration, developers often make their errors easier to parse and make the logs more accessible to testers.