code: public List<M> findByCache(String cacheName, Object key, String sql, Object... paras) {
  		Config config = _getConfig();
  		ICache cache = config.getCache();
  		List<M> result = cache.get(cacheName, key);
  		if (result == null) {
  			result = find(config, sql, paras);
  			cache.put(cacheName, key, result);
  		}
  		return result;
  	}
docs: Find model by cache.
  @see #find(String, Object...)
  @param cacheName the cache name
  @param key the key used to get data from cache
  @return the list of Model