Why it wont let me override addViewControllers method from WebMvcConfigurer interface? - spring-boot

Question

Context:
1 - starting new Spring boot web app;
2 - WebMvcConfig Class implementing WebMvcConfigurer interface
The code is copied from a previous Spring MVC project where it works.
STS suggests to delete the override annotation and deleting does make the error disappear but, my intention is to override the method and also, will it actually work without the override?
import javax.sql.DataSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.lookup.JndiDataSourceLookup;
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.mvc.method.annotation.RequestMappingHandlerMapping;
import org.springframework.web.servlet.view.JstlView;
import org.springframework.web.servlet.view.UrlBasedViewResolver;
#Configuration
#ComponentScan("com.xxxxxx.mwadmin")
#EnableWebMvc
public class WebMvcConfig implements WebMvcConfigurer {
#Bean
public DataSource dataSource(){
final JndiDataSourceLookup dsLookup = new JndiDataSourceLookup();
dsLookup.setResourceRef(true);
DataSource dataSource = dsLookup.getDataSource("jdbc/springdb");
return dataSource;
}
#Bean
public RequestMappingHandlerMapping requestMappingHandlerMapping() {
RequestMappingHandlerMapping rmhm = new RequestMappingHandlerMapping();
rmhm.setUseSuffixPatternMatch(true);
rmhm.setUseTrailingSlashMatch(true);
return rmhm;
}
#Bean
public UrlBasedViewResolver urlBasedViewResolver() {
UrlBasedViewResolver resolver = new UrlBasedViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
resolver.setViewClass(JstlView.class);
return resolver;
}
#Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/").setViewName("home");
}
}
Problem:
On my config Class STS showing the error "The method addViewControllers(ViewControllerRegistry) of type WebMvcConfig must override a superclass method".