static <A, B> LinkedHashMap<A, B> syncMapPut2_createLinkedHashMap(LinkedHashMap<A, B> map, A key, B value) {
  if (key != null)
    if (value != null) {
      if (map == null) map = new LinkedHashMap;
      synchronized(collectionMutex(map)) { map.put(key, value); }
    } else if (map != null) synchronized(collectionMutex(map)) { map.remove(key); }
  ret map;
}

Began life as a copy of #1024463