localhost: 8080 does not work

As you can see, I decided to dispense with the web.xml

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;


public class SpringWebInicializador implements WebApplicationInitializer {

    public void onStartup(ServletContext contenedor) throws ServletException {


        AnnotationConfigWebApplicationContext contexto = new AnnotationConfigWebApplicationContext();
        contexto.register(ConfiguracionSpring.class);
        contexto.setServletContext(contenedor);

        ServletRegistration.Dynamic servlet = contenedor.addServlet("dispatcher", new DispatcherServlet(contexto));
        servlet.setLoadOnStartup(0);
        servlet.addMapping("/");
    }

}

Here I put the code for the spring configurator

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

@EnableWebMvc
@ComponentScan("lacasadelasabuelas.*")
@Configuration
public class ConfiguracionSpring implements WebMvcConfigurer {

    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/").setViewName("index");
    }

    @Bean
    // Only used when running in embedded servlet
    public DispatcherServlet dispatcherServlet() {
        return new DispatcherServlet();
    }

    public void configureDefaultServletHandling(
            DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Bean
     public InternalResourceViewResolver getInternalResourceViewResolver() {
     System.out.println("llega");
     InternalResourceViewResolver resolver = new InternalResourceViewResolver();
     resolver.setPrefix("/WEB-INF/jsp/");
     resolver.setSuffix(".jsp");
     return resolver;

    }
}

But at the time of doing a requestMappging to the address: localhost: 8080 / hello I get a 404

@Controller
public class MainController {

    @RequestMapping("/hola")
    public String hola() {

        return "index";
    }