*/
    @CanIgnoreReturnValue
    @Deprecated
    @Override
    @DoNotCall("Always throws UnsupportedOperationException")
    public final boolean addAll(Collection<? extends E> newElements) {
      throw new UnsupportedOperationException();
    }

    /**
     * Guaranteed to throw an exception and leave the collection unmodified.
     *
     * @throws UnsupportedOperationException always