Error and Exception Handling
When it comes to programming, errors and other unexpected occurrences will undoubtedly creep into even the most trivial applications. Some of these errors are programmer induced, the result of mistakes made during the development process. Others are user induced, caused by the end user’s unwillingness or inability to conform to application constraints such as not entering a syntactically valid e-mail address. Still others are due to events likely outside of your control entirely, such as temporary inaccessibility of a database or network connection. Yet regardless of the error’s origin, your application must be able to react to such unexpected errors in a graceful fashion, hopefully doing so without losing data or crashing. In addition, your application should be able to provide users with the feedback necessary to understand the reason for such errors and potentially adjust their behavior accordingly. Some warnings or errors should also lead to notification of system administrators or developers, allowing them to take action and correct the problem.