code: public static <K, V> Cache<K, V> createCache(String cacheName) {
  		return createCache(cacheName, DEFAULT_TTL, DEFAULT_CLEANUP_INTERVAL/*, application, layer*/);
  	}
docs: Retrieves a cache from the current layer or creates it.
  Only a root request will be able to embed the constructed cache in the
  application.
  
  @param cacheName cache service ID
  @return