@Override
	public boolean keyExists(final String key) {
		boolean exist = doKeyExists(key);

		if (exist) {
			return exist;
		}

		HighLevelCacheCallback callback = new HighLevelCacheCallback() {

			@Override
			protected Object doInCache(Cache cache) {
				return cache.keyExists(key);
			}
		};
		exist = (Boolean) callback.process(highLevelCache);

		return exist;
	}