@Override
 public V putIfAbsent(K key, V value) {
   return putCommand.putIfAbsent(contexts.get(), key, value);
 }
 @Override
 @SuppressWarnings("unchecked")
 public void putAll(Map<? extends K, ? extends V> map) {
   putCommand.putAll(contexts.get(), (Map<K, V>) map);
 }