build method

Implementation

BuiltSetMultimap<K, V> build() {
  if (_builtMapOwner == null) {
    for (var key in _builderMap.keys) {
      var builtSet = _builderMap[key]!.build();
      if (builtSet.isEmpty) {
        _builtMap.remove(key);
      } else {
        _builtMap[key] = builtSet;
      }
    }

    _builtMapOwner = _BuiltSetMultimap<K, V>.withSafeMap(_builtMap);
  }
  return _builtMapOwner!;
}