Is it possible to send all Java Exceptions by email?

Question

I have a Java Web application, using Spring MVC, and would like to email all Exceptions released on the system.

Is it possible to do that? Set up a default email to receive all Exceptions and stacktrace, so I can keep track of possible errors that happen?

Answer 1

Using Spring MVC

Spring MVC provides a way to handle exceptions, the annotation @Exceptionhandler . For each controller we can define a method that is called when a certain exception is thrown.

First you need to create a class and place the annotation @Controlleradvice. This annotation is used to define methods @ExceptionHandler, @InitBinder and @ModelAttribute which apply to all methods noted with @RequestMapping.

@ControllerAdvice
public class SendMailExceptionHandler {

    @Autowired
    protected SendMailService sendMailService;

    @ExceptionHandler(Exception.class)
    public ModelAndView exceptionHanlder(Exception  ex) {
        String mensagem = "Ocorreu um erro no sistema xyz: " + ex.getMessage();
        sendMailService.send(mensagem);

        ModelAndView mv = new ModelAndView();
        mv.addObject("exception", exception);
        mv.addObject("url", req.getRequestURL());
        mv.setViewName("error");

        return mv;
    }
}

In the @ExceptionHandler you pass which class of Exception that method will intercept in controllers.

The advantage is that you don’t need to use try catch in your controllers and in addition to sending the email the method will redirect the user to a page you want, a default error page for example.

This approach does not capture errors from other calls that do not pass through the controller, for example you have an automatic execution from time to time that ends up generating an exception and in this case the @ExceptionHandler will not capture.

Using AOP
With Spring, you can write an Interceptor AOP :

@Aspect
public class ErrorInterceptor{

   SendMailService sendMailService;

@AfterThrowing(pointcut = "execution(* br.com..* (..))", throwing = "ex")
public void errorInterceptor(Exception ex) {
    if (logger.isDebugEnabled()) {
        logger.debug("Interceptor inicializado");
    }


    String mensagem = "Ocorreu um erro no sistema xyz. " + ex.getMessage();
    sendMailService.send(mensagem);


    if (logger.isDebugEnabled()) {
        logger.debug("Interceptor finalizado.");
    }
}
}

With the AOP you can intercept the exceptions that occur in a given package. If you do not know AOP recommend reading the documentation.

Sources: https://stackoverflow.com/questions/10947933/aop-exception-handling https://spring.io/blog/2013/11/01/exception-handling-in-spring-mvc