code: @Override
  	public int size() {
  		int count = 0;
  		for (Map<N, Map<K, S>> namespaceMap : state) {
  			if (null != namespaceMap) {
  				for (Map<K, S> keyMap : namespaceMap.values()) {
  					if (null != keyMap) {
  						count += keyMap.size();
  					}
  				}
  			}
  		}
  		return count;
  	}
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