throw error when midi not connected

[mrbbp]

hello, it not really an issue.
i would like to intercept the error when no midi are connected to computer and let the script to follow his way.
with the try catch instruction, we have to provide exception, but i'm not able to designate the type of error for the catchparameter.
any help?
thanks

[mrbbp]

The MidiBus Warning: The chosen input device numbered [1] was not added because it doesn't exist
The MidiBus Warning: The chosen output device numbered [2] was not added because it doesn't exist

and script stop without error.

try {
  // List all available Midi devices on STDOUT. This will show each device's index and name.
  MidiBus.list(); 
  //                   Parent In Out
  //                     |    |  |
  //myBus = new MidiBus(this, 0, 1);
  //Create a new MidiBus using the device index to select the Midi input and output devices respectively.
  delay(100);
  myBus = new MidiBus(this, 1, 2);
  // initialise les valeurs du device
  myBus.sendNoteOff(new Note(0,64,127));
  } catch (NullPointerException e) {
    e.printStackTrace();
  }

how can we test code without a midi device connected to computer?