final List<Entry<K, V>> entries;
    @Nullable Comparator<? super V> valueComparator;

    public Builder() {
      this.entries = Lists.newArrayList();
    }

    Builder(int initCapacity) {
      this.entries = Lists.newArrayListWithCapacity(initCapacity);
    }

    @CanIgnoreReturnValue
    public Builder<K, V> put(K key, V value) {
      entries.add(entryOf(key, value));
      return this;

      if (entries instanceof Collection) {
        ensureCapacity(size + ((Collection<?>) entries).size());
      }
      for (Entry<? extends K, ? extends V> entry : entries) {
        put(entry);
      }
      return this;
    }

    /**
     * Configures this {@code Builder} to order entries by value according to the specified
     * comparator.

    Builder(int initialCapacity) {
      this.entries = new @Nullable Entry[initialCapacity];
      this.size = 0;
      this.entriesUsed = false;
    }

    private void ensureCapacity(int minCapacity) {
      if (minCapacity > entries.length) {
        entries =
            Arrays.copyOf(
                entries, ImmutableCollection.Builder.expandedCapacity(entries.length, minCapacity));
        entriesUsed = false;