spring mvc @ExceptionHandler method get same view

Question

My problem is that I want to create an @ExceptionHandler method that will capture all un-handled exceptions. Once captured I would like to redirect to the current page instead of specifying a separate page just to display error.

Basically how do I get the value of someview returned by somemethod and set it dynamically in the method unhandledExceptionHandler below.

@ExceptionHandler(Exception.class)
protected ModelAndView unhandledExceptionHandler(Exception ex){
    System.out.println("unhandle exception here!!!");
    ModelAndView mv = new ModelAndView();
    mv.setViewName("currentview");
    mv.addObject("UNHANDLED_ERROR", "UNHANDLED ERROR. PLEASE CONTACT SUPPORT. "+ex.getMessage());
    return mv;
}



@RequestMapping(value = "/somepage", method = RequestMethod.GET)
public String somemethod(HttpSession session) throws Exception {
    String abc = null;
    abc.length();
    return "someview";
}

So in JSP I can render this error message back into the current page something like that.

<c:if test="${not empty UNHANDLED_ERROR}">
    <div class="messageError"> ${UNHANDLED_ERROR}</div>
</c:if>

Answer 1

I dont think you can do this without modifying all of your handler methods. However you can try to do this in a "pretty" way:

1) You can define your own annotation which will accept target view name as a parameter (e.g. @ExceptionView)

2) Next thing to do is marking your handler methods with it, e.g.:

@ExceptionView("someview")
@RequestMapping(value = "/somepage", method = RequestMethod.GET)
    public String somemethod(HttpSession session) throws Exception {
    String abc = null;
    abc.length();
    return "someview";
}

3) After that you can do something like this in exception handler:

@ExceptionHandler(Exception.class)
protected ModelAndView unhandledExceptionHandler(Exception ex, HandlerMethod hm) {
    String targetView;
    if (hm != null && hm.hasMethodAnnotation(ExceptionView.class)) {
        targetView = hm.getMethodAnnotation(ExceptionView.class).getValue();
    } else {
        targetView = "someRedirectView"; // kind of a fallback
    }
    ModelAndView mv = new ModelAndView();
    mv.setViewName(targetView);
    mv.addObject("UNHANDLED_ERROR", "UNHANDLED ERROR. PLEASE CONTACT SUPPORT. "+ex.getMessage());
    return mv;
}

Answer 2

I have not tried this out, but based on the documentation here, we can get the request object in the exception handler. We may not be able to get the view linked to the URL. Getting the view from the URL, and the state/model of the view will be the tricky part.

  @ExceptionHandler(Exception.class)
  public ModelAndView handleError(HttpServletRequest req, Exception ex) {
    logger.error("Request: " + req.getRequestURL() + " raised " + ex);

    ModelAndView mav = new ModelAndView();
    mav.addObject("exception", ex);
    mav.addObject("url", req.getRequestURL());
    mav.setViewName("error");
    return mav;
  }