}
    }

    @Override
    public NavigableMap<K, V> headMap(K toKey, boolean inclusive) {
      synchronized (mutex) {
        return navigableMap(delegate().headMap(toKey, inclusive), mutex);
      }
    }

    @Override
    public SortedMap<K, V> headMap(K toKey) {
      return headMap(toKey, false);
    }

    @Override
    @CheckForNull

    val newConnectionsNeeded: Int

    while (true) {
      val oldMap = this.addressStates
      val newMap = oldMap + (address to state)
      if (addressStatesUpdater.compareAndSet(this, oldMap, newMap)) {
        val oldPolicyMinimumConcurrentCalls = oldMap[address]?.policy?.minimumConcurrentCalls ?: 0

      return fromMap().floorKey(key);
    }

    @Override
    public NavigableMap<K, V2> headMap(@ParametricNullness K toKey) {
      return headMap(toKey, false);
    }

    @Override
    public NavigableMap<K, V2> headMap(@ParametricNullness K toKey, boolean inclusive) {
      return transformEntries(fromMap().headMap(toKey, inclusive), transformer);
    }

    @Override
    @CheckForNull