}

  ImmutableMapEntry(ImmutableMapEntry<K, V> contents) {
    super(contents.getKey(), contents.getValue());
    // null check would be redundant
  }

  @CheckForNull
  ImmutableMapEntry<K, V> getNextInKeyBucket() {
    return null;
  }

  @CheckForNull
  ImmutableMapEntry<K, V> getNextInValueBucket() {
    return null;
  }

  /**

      boolean throwIfDuplicateKeys)
      throws BucketOverflowException {
    int bucketSize = 0;
    for (; keyBucketHead != null; keyBucketHead = keyBucketHead.getNextInKeyBucket()) {
      if (keyBucketHead.getKey().equals(key)) {
        if (throwIfDuplicateKeys) {
          checkNoConflict(/* safe= */ false, "key", keyBucketHead, key + "=" + newValue);
        } else {