* @throws ExecutionError if the loading thread throws an error
     */
    V waitForValue() throws ExecutionException;

    /** Returns the weight of this entry. This is assumed to be static between calls to setValue. */
    int getWeight();

    /**
     * Returns the entry associated with this value reference, or {@code null} if this value
     * reference is independent of any entry.

   * set does not contain {@code null}, because the view cannot stop {@code null} from being added
   * to the set.
   *
   * <p><b>Warning:</b> This method assumes that for any instance {@code k} of key type {@code K},
   * {@code k.equals(k2)} implies that {@code k2} is also of type {@code K}. Using a key type for

     * @throws ExecutionError if the loading thread throws an error
     */
    V waitForValue() throws ExecutionException;

    /** Returns the weight of this entry. This is assumed to be static between calls to setValue. */
    int getWeight();

    /**
     * Returns the entry associated with this value reference, or {@code null} if this value
     * reference is independent of any entry.