****Main Class****public void whatever(){ //already have SourceDataLine line; declared in the main classSourceDataLine line = null;////////////////////we'll call this line "key point"try { line = (SourceDataLine) AudioSystem.getLine(info); line.open(audioFormat); } catch (LineUnavailableException e) { e.printStackTrace(); }System.out.println("line 1st time: " + line);}***Inner Class***class PlayThread implements Runnable{System.out.println("line 2nd time: " + line); //this we be NULL unless "key point" is commented out //which in turn causes the program not to function}***END Inner Class*******END Main Class****