code: public int getMnemonic() {
          int mnemonic = KeyEvent.VK_UNDEFINED;
          if (!MAC_OS_X) {
              int index = getMnemonicIndex();
              if ((index >= 0) && ((index + 1) < myAnnotatedString.length())) {
                  mnemonic = Character.toUpperCase(myAnnotatedString.charAt(index + 1));
              }
          }
          return mnemonic;
      }
docs: Return the appropriate mnemonic character for this string. If no mnemonic
  should be displayed, KeyEvent.VK_UNDEFINED is returned.
  
  @return the Mnemonic character, or VK_UNDEFINED if no mnemonic should be
  set