spring boot static content

I’m having trouble serving up static content with Spring Boot.

I’m using the default config location(s): src/main/resources/static/css and src/main/resources/static/js.

When the pages load I get a 404 for all the static content. I even added permitAll to my security settings.

@Override
protected void configure(HttpSecurity http) throws Exception {
  http
    .authorizeRequests()    
      .antMatchers("/css/**","/js/**").permitAll()
      .antMatchers("/services/**").hasRole("PREAUTH_USER")
      .antMatchers("/", "/dashboard").permitAll()
      .anyRequest().authenticated()
    .and()
      .formLogin().loginPage("/login")
      .permitAll()
    .and()
      .logout()
      .permitAll();
}

My resource handler:

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) { 
  registry.addResourceHandler("/**").addResourceLocations("/");
}

…when I hit login my CSS is returing a 404: http://localhost:8080/login

Here are the response headers:

Request URL:http://localhost:8080/css/preauth.css
Request Method:GET
Status Code:404 
Remote Address:[::1]:8080
Referrer Policy:no-referrer-when-downgrade
Response Headers
view source
Cache-Control:no-cache, no-store, max-age=0, must-revalidate
Content-Type:application/json;charset=UTF-8
Date:Fri, 01 Sep 2017 17:04:59 GMT
Expires:0
Pragma:no-cache
Transfer-Encoding:chunked
X-Content-Type-Options:nosniff
X-Frame-Options:DENY
X-XSS-Protection:1; mode=block
Request Headers
view source
Accept:text/css,*/*;q=0.1
Accept-Encoding:gzip, deflate, br
Accept-Language:en-US,en;q=0.8
Connection:keep-alive
Cookie:JSESSIONID=D1399529A7AD61D0FA67ECF0343D3A03
Host:localhost:8080
Referer:http://localhost:8080/login
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36

The issue seems to be when I extended WebMvcConfigurationSupport in my appConfig class(I needed to configure messageconverters), WebMvcAutoConfiguration is disabled. So I had to add

private static final String[] CLASSPATH_RESOURCE_LOCATIONS = {
        "classpath:/META-INF/resources/", "classpath:/resources/",
        "classpath:/static/", "classpath:/public/" };

And

   @Override
  public void addResourceHandlers(ResourceHandlerRegistry registry) {
if (!registry.hasMappingForPattern("/webjars/**")) {
    registry.addResourceHandler("/webjars/**").addResourceLocations(
            "classpath:/META-INF/resources/webjars/");
}
if (!registry.hasMappingForPattern("/**")) {
    registry.addResourceHandler("/**").addResourceLocations(
            CLASSPATH_RESOURCE_LOCATIONS);
}

EDIT:
The above code is not required. I changed my config class to extend WebMvcConfigurerAdapter and the above changes are not required..See the comment below from @AndyWilkinson