Update: Jan-2019
First create public folder under resources and create index.html file. Use WebMvcConfigurer instead of WebMvcConfigurerAdapter.
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 WebAppConfig implements WebMvcConfigurer {
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/").setViewName("forward:/index.html");
}
}