*       thoroughly as possible.
 *   <li><b>bit-dispersing:</b> masking out any <i>single bit</i> from a hash code should yield only
 *       the expected <i>twofold</i> increase to all collision rates. Informally, the "information"
 *       in the hash code should be as evenly "spread out" through the hash code's bits as possible.

 *       thoroughly as possible.
 *   <li><b>bit-dispersing:</b> masking out any <i>single bit</i> from a hash code should yield only
 *       the expected <i>twofold</i> increase to all collision rates. Informally, the "information"
 *       in the hash code should be as evenly "spread out" through the hash code's bits as possible.

    }
  }

  /**
   * Returns the result of the input {@code Future}, which must have already completed.
   *
   * <p>The benefits of this method are twofold. First, the name "getDone" suggests to readers that
   * the {@code Future} is already done. Second, if buggy code calls {@code getDone} on a {@code