code: @Override
  	public Map<String, VariantSet> getAvailableVariants(String mapping) {
  
  		Map<String, VariantSet> availableVariants = new HashMap<>();
  		String skinRootDir = getSkinRootDir(mapping, skinMapping.keySet());
  		if (skinRootDir != null) {
  			Map<String, VariantSet> variantSets = skinMapping.get(skinRootDir);
  			for (VariantSet variantSet : variantSets.values()) {
  				availableVariants.put(variantSet.getType(), variantSet);
  			}
  		}
  
  		return availableVariants;
  	}
docs: /*
  (non-Javadoc)
  
  @see
  net.jawr.web.resource.bundle.generator.variant.VariantResourceGenerator
  #getAvailableVariants(java.lang.String)