This application has no explicit mapping for error

Question

I used maven to follow the tutorial: https://spring.io/guides/gs/uploading-files/ step by step. All the codes that are used were copied from this tutorial.

The App runs, but I get the error:

Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback. Tue Jun 30 17:24:02 CST 2015 There was an unexpected error (type=Not Found, status=404). No message available

Can someone help me with this issue?

Answer 1

One of the reason this error coccured is that you forgot the @RestController annotation on top of your controller class import, import org.springframework.web.bind.annotation.RestController;

Refer the simple example below:

import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.RequestMapping;

@RestController
public class HelloController {
@RequestMapping("/")
    public String index() {
        return "Greetings from Spring Boot!";
    }

}

The other cause of this issue is that you might be missing the @Configuration annotation in the MvcConfig class which basically does the mapping for ViewControllers and setViewNames.

Content of the file :

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
**@Configuration**
public class MvcConfig implements WebMvcConfigurer{
   public void addViewControllers(ViewControllerRegistry registry)
   {
      registry.addViewController("/").setViewName("login");
      registry.addViewController("/login").setViewName("login");
      registry.addViewController("/dashboard").setViewName("dashboard");
   }
}

I hope this helps.