404 error redirect in Spring with java config

Question

As you know, in XML, the way to configure this is:

    404
    /my-custom-page-not-fo         


        

Answer 1

Simple answer for 100% free xml:

1. Set properties for DispatcherServlet

   public class SpringMvcInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
   
       @Override
       protected Class[] getRootConfigClasses() {
           return new Class[] { RootConfig.class  };
       }
   
       @Override
       protected Class[] getServletConfigClasses() {
           return new Class[] {AppConfig.class  };
       }
   
       @Override
       protected String[] getServletMappings() {
           return new String[] { "/" };
       }
   
       @Override
       protected void customizeRegistration(ServletRegistration.Dynamic registration) {
           boolean done = registration.setInitParameter("throwExceptionIfNoHandlerFound", "true"); // -> true
           if(!done) throw new RuntimeException();
       }
   
   }
   

2. Create @ControllerAdvice:

   @ControllerAdvice
   public class AdviceController {
   
       @ExceptionHandler(NoHandlerFoundException.class)
       public String handle(Exception ex) {
           return "redirect:/404";
       }
   
       @RequestMapping(value = {"/404"}, method = RequestMethod.GET)
       public String NotFoudPage() {
           return "404";
   
       }
   }