Error if I do, Error if I dont!!!

Question

Hey, I'm having problems with my code.
if (midiIOIn == thisThread) {
               try {
                    Transmitter getTrans = MidiSystem.getTransmitter();
                    Sequencer setSeq = MidiSystem.getSequencer();
                    MidiEvent recMSG;
                    MidiMessage getMSG1 = recMSG.getMessage();
                    int recStatus = getMSG1.getStatus();
                    byte[] getMSG2 = getMSG1.getMessage();
                    String statusString = Integer.toString(recStatus);
                    String messageString = getMSG2.toString();
                    gui.midiInTextField.setText(statusString);
                  gui.midiStatusTextField.setText("Data Received");
               catch (MidiUnavailableException ex1) {
                   System.out.println("FAIL");
           }The line: MidiEvent recMSG; gives me the error variable has not been initialized*, when I intialize it with *'= null'* it goes away and I can compile my program, but when I hit the button to receive MIDI information I get a +'NullPointerException'+ on the next line down.
Can anyone help me with this problem?
Greatly appreciated,
Tom

Answer 1

Maybe you need to have this variable refer to some non-null object? Just a thought.
Sorry, not meaning to be smug (OK, maybe a little), but what do you expect will happen if you do:
MidiEvent recMSG = null;
MidiMessage getMSG1 = recMSG.getMessage();You're trying to call a method on a null object, so of course you'll have a NPE. The solution: get a decent MidiEvent object first before trying to call a method on it. I'm not familiar with Java Midi programming, but it almost sounds as if a MidiEvent object would be passed as a parameter to the method for a Midi-Listener of some type. I'm sure the API will show you the way.
Edited by: Encephalopathic on Dec 23, 2009 2:12 PM