code: public final boolean remove(K key) {
          P pool =  map.remove(checkNotNull(key, "key"));
          if (pool != null) {
              pool.close();
              return true;
          }
          return false;
      }
docs: Remove the {@link ChannelPool} from this {@link AbstractChannelPoolMap}. Returns {@code true} if removed,
  {@code false} otherwise.
  
  Please note that {@code null} keys are not allowed.