if (title == null || title.charAt(index) != mnemonicKey)
if (title == null || mnemonicKey == 0 || title.charAt(index) != mnemonicKey)
    public void setDisplayedMnemonicIndex(int index)                                   throws IllegalArgumentException    {      if (index < -1 || title != null && index >= title.length())	throw new IllegalArgumentException();      if (title == null || title.charAt(index) != mnemonicKey)	index = -1;      underlinedChar = index;    }