StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
text
Body
copied!<p>You should almost never catch the top level Exception.</p> <p>In most cases you should catch and handle the most specific exception possible and only if there is something useful you can do with it.</p> <p>The exception (haha) to this is if you are catching for logging and re-throw the exception, then it is sometimes OK to catch a top level Exception, log it and rethrow it.</p> <p>You should almost never catch a top level Exception and swallow it. This is because if you are catching a top level exception you don't really know what you are handling; absolutly anything could have caused it so you will almost certainly not be able to do anything that will handle every single failure case correctly. There probably are some failures that you may just want to silently handle and swallow, but by just swallowing top level Exceptions you'll also be swallowing a whole bunch that really should have been thrown upwards for your code to handle higher up. In your code example what you probably want to do is handle a SQLException and log+swallow that; and then for an Exception, log and rethrow it. This covers yourself. You're still logging all exception types, but your only swallowing the fairly predictable SQLException which indicates problems with your SQL/database.</p> <p>A common practise is to only every handle exceptions that you can actually resolve at that point, if you can't resolve it at that point in code then you allow it to bubble upwards. If you can't resolve it at the next level up, allow it to continue up. If it reaches the top unhandled then display a polite appology to the user (perhaps attempt a quick autosave) and close the app. It's generally considered worse to allow an app to continue running after an unhandled exception because you can't predict the state of the application as something exceptional has occured. It's better just to shutdown and restart the app to get back to an expected state.</p>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload