}
      // careful of overflow!
      int newCapacity = oldCapacity + (oldCapacity >> 1) + 1;
      if (newCapacity < minCapacity) {
        newCapacity = Integer.highestOneBit(minCapacity - 1) << 1;
      }
      if (newCapacity < 0) {
        newCapacity = Integer.MAX_VALUE; // guaranteed to be >= newCapacity
      }
      return newCapacity;
    }

    /**

      }
      // careful of overflow!
      int newCapacity = oldCapacity + (oldCapacity >> 1) + 1;
      if (newCapacity < minCapacity) {
        newCapacity = Integer.highestOneBit(minCapacity - 1) << 1;
      }
      if (newCapacity < 0) {
        newCapacity = Integer.MAX_VALUE; // guaranteed to be >= newCapacity
      }
      return newCapacity;
    }

    /**

      }
      // careful of overflow!
      int newCapacity = oldCapacity + (oldCapacity >> 1) + 1;
      if (newCapacity < minCapacity) {
        newCapacity = Integer.highestOneBit(minCapacity - 1) << 1;
      }
      if (newCapacity < 0) {
        newCapacity = Integer.MAX_VALUE; // guaranteed to be >= newCapacity
      }
      return newCapacity;
    }

    /**

      }
      // careful of overflow!
      int newCapacity = oldCapacity + (oldCapacity >> 1) + 1;
      if (newCapacity < minCapacity) {
        newCapacity = Integer.highestOneBit(minCapacity - 1) << 1;
      }
      if (newCapacity < 0) {
        newCapacity = Integer.MAX_VALUE; // guaranteed to be >= newCapacity
      }
      return newCapacity;
    }

    /**

    if (size > queue.length) {
      int newCapacity = calculateNewCapacity();
      Object[] newQueue = new Object[newCapacity];
      arraycopy(queue, 0, newQueue, 0, queue.length);
      queue = newQueue;
    }
  }

  /** Returns ~2x the old capacity if small; ~1.5x otherwise. */
  private int calculateNewCapacity() {
    int oldCapacity = queue.length;
    int newCapacity =

    if (size > queue.length) {
      int newCapacity = calculateNewCapacity();
      Object[] newQueue = new Object[newCapacity];
      arraycopy(queue, 0, newQueue, 0, queue.length);
      queue = newQueue;
    }
  }

  /** Returns ~2x the old capacity if small; ~1.5x otherwise. */
  private int calculateNewCapacity() {
    int oldCapacity = queue.length;
    int newCapacity =

   * hashtable size to reduce expensive rehashing. Otherwise the returned power of 2 is 2x the
   * current hashtable size.
   */
  static int newCapacity(int mask) {
    return ((mask < 32) ? 4 : 2) * (mask + 1);
  }

  /** Returns the hash prefix given the current mask. */
  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

   * hashtable size to reduce expensive rehashing. Otherwise the returned power of 2 is 2x the
   * current hashtable size.
   */
  static int newCapacity(int mask) {
    return ((mask < 32) ? 4 : 2) * (mask + 1);
  }

  /** Returns the hash prefix given the current mask. */
  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

    }

    private void ensureCapacity(int minCapacity) {
      if (minCapacity > keys.length) {
        int newCapacity = ImmutableCollection.Builder.expandedCapacity(keys.length, minCapacity);
        this.keys = Arrays.copyOf(keys, newCapacity);
        this.values = Arrays.copyOf(values, newCapacity);
      }
    }

    /**