Spring MVC, redirect to error after Rest call exception - spring

Question

I'm performing a Rest request in one of my controllers and I'd like to redirect to my error view if the request went wrong (404, 503 ...)
My controller calls this function :
public String functionTest(){
String date, res;
String url = "myRestUrl/{param}";
Map<String, String> uriParams = new HashMap<>();
uriParams.put("param", "param");
UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(url);
HttpEntity<String> request = new HttpEntity<>(createHeaders());
RestTemplate restTemplate = new RestTemplate();
restTemplate.setErrorHandler(new RestErrorHandler());
ResponseEntity<String> response = restTemplate.exchange(builder.buildAndExpand(uriParams).toUri(), HttpMethod.GET, request, String.class);
res= response.getBody().getMyResult();
return res;
}
And here is my Rest error handler :
public class RestErrorHandler extends DefaultResponseErrorHandler {
#Override
public void handleError(ClientHttpResponse response) throws IOException {
//Here I need to use a ModelAndView to redirect to error view but I'm not anymore in my controller
}
}
I guess I'm doing it wrong, do you have any solutions ?

Answer 1

Here is a rather simplistic way to achieve what you need. If you would like more control/flexibility, refer to this Spring blog article.
In your (client) RestErrorHandler:
public class RestErrorHandler extends DefaultResponseErrorHandler {
#Override
public void handleError(ClientHttpResponse response)
throws IOException {
// Do some stuff here ...
// This could be your own exception, for example.
throw new IOException();
}
}
Then in your controller (or refer to the article above if you want other options):
// Your requestMappings here ...
#ExceptionHandler(Exception.class)
public ModelAndView handleError(HttpServletRequest req, Exception ex) {
ModelAndView mav = new ModelAndView();
// Do stuff and redirect to your error view.
return mav;
}
EDIT: Another solution would be to catch Spring's RestClientException, which is a RuntimeException thrown by RestTemplate when it encounters an error:
try {
restTemplate.exchange(...);
} catch (RestClientException ex) {
// Do stuff here ...
}