Displaying application exceptions in a nice way

You can use the ExceptionFilter as a global filter for that. Just set it up in the front of all other filters, so it will trap any exceptions that happen after him:

After placing some info about the exception in the action output, the ExceptionFilter returns the EXCEPTION result. Therefore you should define a global consequence that will be a forward to the page designed to exception and perhaps a sorry message to the user:

Now in the error.jsp page, you can get the following values from the action output: