Swing Hacks

Build an Audio Waveform Display #75

Chapter 10, Audio

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385

HACK

Seeing Is Believing

Now, you’re ready to run the hack. The main( ) method shown here is the

simulator code. Notice the creation of the

AudioInputStream and the cre-

ation of the container with the stream. All painting and management of

SingleWaveformPanels is encapsulated within the separate panel classes:

public static void main(String[] args) {

try {

JFrame frame = new JFrame("Waveform Display Simulator");

frame.setBounds(200,200, 500, 350);

File file = new File(args[0]);

AudioInputStream audioInputStream

= AudioSystem.getAudioInputStream(file);

WaveformPanelContainer container = new WaveformPanelContainer( );

container.setAudioToDisplay(audioInputStream);

frame.getContentPane().setLayout(new BorderLayout( ));

frame.getContentPane( ).add(container, BorderLayout.CENTER);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.show( );

frame.validate( );

frame.repaint( );

} catch (Exception e){

e.printStackTrace( );

}

}

Then, just make sure to pass the audio filename in at the command line. Use

something like this:

java WaveformDisplaySimulator chord.wav

private JComponent createChannelDisplay(

SingleWaveformPanel waveformPanel,

int index) {

JPanel panel = new JPanel(new BorderLayout( ));

panel.add(waveformPanel, BorderLayout.CENTER);

JLabel label = new JLabel("Channel " + ++index);

panel.add(label, BorderLayout.NORTH);

return ...