Redirect to an external URL from controller action in Spring MVC

You can do it with two ways.

First:

@RequestMapping(value = "/redirect", method = RequestMethod.GET)public void method(HttpServletResponse httpServletResponse) {    httpServletResponse.setHeader("Location", projectUrl);    httpServletResponse.setStatus(302);}

Second:

@RequestMapping(value = "/redirect", method = RequestMethod.GET)public ModelAndView method() {    return new ModelAndView("redirect:" + projectUrl);}

You can use the RedirectView. Copied from the JavaDoc:

View that redirects to an absolute, context relative, or current request relative URL

Example:

@RequestMapping("/to-be-redirected")public RedirectView localRedirect() {    RedirectView redirectView = new RedirectView();    redirectView.setUrl("http://www.yahoo.com");    return redirectView;}

You can also use a ResponseEntity, e.g.

@RequestMapping("/to-be-redirected")public ResponseEntity<Object> redirectToExternalUrl() throws URISyntaxException {    URI yahoo = new URI("http://www.yahoo.com");    HttpHeaders httpHeaders = new HttpHeaders();    httpHeaders.setLocation(yahoo);    return new ResponseEntity<>(httpHeaders, HttpStatus.SEE_OTHER);}

And of course, return redirect:http://www.yahoo.com as mentioned by others.

Looking into the actual implementation of UrlBasedViewResolver and RedirectView the redirect will always be contextRelative if your redirect target starts with /. So also sending a //yahoo.com/path/to/resource wouldn't help to get a protocol relative redirect.

So to achieve what you are trying you could do something like:

@RequestMapping(method = RequestMethod.POST)public String processForm(HttpServletRequest request, LoginForm loginForm,                           BindingResult result, ModelMap model) {    String redirectUrl = request.getScheme() + "://www.yahoo.com";    return "redirect:" + redirectUrl;}