重定向不适用于 Spring 引导应用程序中的 Thymeleaf

Question

I'am trying to create a simple app on Spring Boot: Controller:

 @Controller
 public class RootController {

    @RequestMapping ("/")
    public String root() {
         return "login";
    }

    @RequestMapping(path = "/joinChart", method = RequestMethod.GET)
    public String joinChart(@RequestParam (defaultValue = "") String username) {
          return "redirect:chat?username=" + username;
    }
 }

root-method is working well. But when I try to redirect on login-page, it return 404-ERROR.

Answer 1

When you do

return "login";

in your root() handler method, you're actually just returning a view name (typically handled by a JstlView but here handled by ThymeleafView since you're using Thymeleaf), but that Spring MVC's web infrastructure (with your Servlet web container) will try to find and render.

When you do

return "redirect:chat?username=" + username;

in your joinChart handler method, you're actually returning a redirect view name that the server will render as a 303 response with a Location header. The client will be instructed to send a new request to /chat . If you don't have a request mapping for that, obviously the server will return a 404.

You need to add a request mapping for /chat

@RequestMapping ("/chat")
public String chat() {
     return "chat";
}