code: public Map<String, String> resolveVariants(HttpServletRequest request) {
  
  		Map<String, String> variants = new TreeMap<>();
  		for (VariantResolver resolver : variantResolvers.values()) {
  			String value = resolver.resolveVariant(request);
  			if (value != null) {
  				variants.put(resolver.getVariantType(), value);
  			}
  		}
  
  		return variants;
  	}
docs: Resolve the variants for the request passed in parameter
  
  @param request
  the request
  @return the map of variants defined in the request