"LinkedHashMapImpl",
    "ConcurrentHashMapImpl",
    "CompactHashMapImpl",
    "CompactLinkedHashMapImpl",
    "ImmutableMapImpl",
    "TreeMapImpl",
    "ImmutableSortedMapImpl",
    "MapMakerWeakKeysWeakValues",
    "MapMakerWeakKeysStrongValues",
    "MapMakerStrongKeysWeakValues",
    "MapMakerStrongKeysStrongValues",
    "HashBiMapImpl",
    "ImmutableBiMapImpl"
  })
  String implName;

        ConcurrentMap<K, V> newMap = new MapMaker().weakKeys().makeMap();
        checkState(newMap instanceof MapMakerInternalMap);
        newMap.putAll(map);
        return newMap;
      }
    },
    MapMakerWeakKeysWeakValues {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {
        ConcurrentMap<K, V> newMap = new MapMaker().weakKeys().weakValues().makeMap();