Spring MVC handle Exceptions and how to show in same view - spring

Question

If I handle exceptions with #ControllerAdvice and #ExceptionHandler How can I show error message to user in the same View. For ex. suppose user in "customer/new" view. and invoke "save" action, then it will go to controller and I call methods service layer. but if internal exception occurred in service layer, I want to show error message on same "customer/new" View.
I have written a separate class to handle exceptions as follow.
#ControllerAdvice
public class DefaultControllerHandler {
#ExceptionHandler({MyProjectException.class, DataAccessException.class})
public ResponseEntity<String> handleInternalErrorException(Exception e) {
logger.error(e.getMessage(), e);
return new ResponseEntity<String>(e.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
}
}
Appreciate your ideas.
Thanks!

Answer 1

You can use flash redirect attributes.
#RequestMapping(value = "/administrator/users", method = RequestMethod.POST)
public String adminAddUser(#ModelAttribute("user") #Valid User user, BindingResult bindingResult, Model model, RedirectAttributes redirectAttrs) {
String redirectUrl = "/administrator/users";
try {
userService.save(user);
} catch (YourServiceException e) {
redirectAttrs.addFlashAttribute("errorMessage", "error occured: " + e.getMessage());
redirectAttrs.addFlashAttribute("userObject", user);
redirectUrl = "/administrator/users?form"; // If error - return to same view
}
return "redirect:" + redirectUrl;
}
#RequestMapping(value = "/administrator/users", params = "form", method = RequestMethod.GET, produces = "text/html")
public String adminUsersList(#ModelAttribute("errorMessage") final String errorMessage, #ModelAttribute("userObject") final User user Model model) {
if(user == null) {
user = new User();
}
model.addAttribute("user", user);
if(errorMessage != null) {
model.addAttribure("errorMessage", errorMessage);
}
return "administrator/users/create";
}
In that case you must have section on your users.jsp page to show errorMessaage. Something like this:
<c:if test="${not empty errorMessage}">${errorMessage}</c:if>
If you can fetch url path and redirectAttributes from controller method - you can do this through #ControllerAdvice

Answer 2

The only solution I can think about is make your call to the service layer AJAX and then redirect only if there are no errors, if not display the error message.
It might look something like this in your Javascript file
$("#someButton").click(function(){
//make your ajax call
if (noError){
window.location.href = contextPath+"/somePath";
}
else{
//display your error message
}
});