The default error page configuration according to HttpStatus

@Configuration
public class WebServerStatusConfiguration {

    @Bean
    public ConfigurableServletWebServerFactory webServerFactory() {
        TomcatServletWebServerFactory factory = new TomcatServletWebServerFactory();
        ErrorPage errorPage400 = new ErrorPage(HttpStatus.BAD_REQUEST, "/error/400");
        ErrorPage errorPage401 = new ErrorPage(HttpStatus.UNAUTHORIZED, "/error/401");
        ErrorPage errorPage403 = new ErrorPage(HttpStatus.FORBIDDEN, "/error/403");
        ErrorPage errorPage404 = new ErrorPage(HttpStatus.NOT_FOUND, "/error/404");
        ErrorPage errorPage415 = new ErrorPage(HttpStatus.UNSUPPORTED_MEDIA_TYPE, "/error/415");
        ErrorPage errorPage500 = new ErrorPage(HttpStatus.INTERNAL_SERVER_ERROR, "/error/500");
        factory.addErrorPages(errorPage400, errorPage401, errorPage403, errorPage404, errorPage415, errorPage500);
        return factory;
    }
}

Note: The path is the path controller in the path, not the page.