Explanation of sound clip code

[jarograv]

I have used snippets of code from various sources to compile the following code:

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import java.util.Calendar;

public class ShowImage extends Panel {
    static Calendar cal = Calendar.getInstance(); //gets system time

BufferedImage  image;
private static final String holidaysimages[] = { //declares the image array
  "santa.jpg", "valentine.jpg", "bunny.jpg", "bunny.jpg", "summer.jpg", "summer.jpg", 
  "summer.jpg", "summer.jpg", "turkey.jpg", "turkey.jpg", "turkey.jpg", "santa.jpg"};
private static final String holidayssounds[] = { //declares the sound array
      "santa.wav", "valentine.wav", "easter.wav", "easter.wav", "summer.wav", "summer.wav", 
      "summer.wav", "summer.wav", "turkey.wav", "turkey.wav", "turkey.wav", "santa.wav"};
  public ShowImage() throws Exception {

try {
    String imageName= holidaysimages[cal.get(Calendar.MONTH)]; //uses the month to get the appropriate picture
    File input = new File(imageName);
    image = ImageIO.read(input);
} catch (IOException ie) {
  System.out.println("Error:"+ie.getMessage()); //prints error message if the image does not exist
}
  }

  public void paint(Graphics g) {
g.drawImage( image, 0, 0, null); //displays the image
  }

  static public void main(String args[]) throws Exception {
JFrame frame = new JFrame("Happy Holidays");
Panel panel = new ShowImage();
frame.getContentPane().add(panel);
frame.setSize(500, 500); //sets  frame size
frame.setVisible(true); 

new AePlayWave(holidayssounds[cal.get(Calendar.MONTH)]).start(); //plays the sound
  }
}

import java.io.File; 
import java.io.IOException; 
import javax.sound.sampled.AudioFormat; 
import javax.sound.sampled.AudioInputStream; 
import javax.sound.sampled.AudioSystem; 
import javax.sound.sampled.DataLine; 
import javax.sound.sampled.FloatControl; 
import javax.sound.sampled.LineUnavailableException; 
import javax.sound.sampled.SourceDataLine; 
import javax.sound.sampled.UnsupportedAudioFileException; 

public class AePlayWave extends Thread { 

private String filename;

private Position curPosition;

private final int EXTERNAL_BUFFER_SIZE = 524288; // 128Kb 

enum Position { 
    LEFT, RIGHT, NORMAL
};

public AePlayWave(String wavfile) { 
    filename = wavfile; //gets the file name from main
    curPosition = Position.NORMAL;
} 

public AePlayWave(String wavfile, Position p) { 
    filename = wavfile; //tells the system that the file is a wav file
    curPosition = p;
} 

public void run() { 

    File soundFile = new File(filename);
    if (!soundFile.exists()) { //if the file is not found prints the error
        System.err.println("Wave file not found: " + filename);
        return;
    } 

    AudioInputStream audioInputStream = null;
    try { 
        audioInputStream = AudioSystem.getAudioInputStream(soundFile);
    } catch (UnsupportedAudioFileException e1) { 
        e1.printStackTrace();
        return;
    } catch (IOException e1) { 
        e1.printStackTrace();
        return;
    } 

    AudioFormat format = audioInputStream.getFormat();
    SourceDataLine auline = null;
    DataLine.Info info = new DataLine.Info(SourceDataLine.class, format);

    try { 
        auline = (SourceDataLine) AudioSystem.getLine(info);
        auline.open(format);
    } catch (LineUnavailableException e) { 
        e.printStackTrace();
        return;
    } catch (Exception e) { 
        e.printStackTrace();
        return;
    } 

    if (auline.isControlSupported(FloatControl.Type.PAN)) { 
        FloatControl pan = (FloatControl) auline
                .getControl(FloatControl.Type.PAN);
        if (curPosition == Position.RIGHT) 
            pan.setValue(1.0f);
        else if (curPosition == Position.LEFT) 
            pan.setValue(-1.0f);
    } 

    auline.start();
    int nBytesRead = 0;
    byte[] abData = new byte[EXTERNAL_BUFFER_SIZE];

    try { 
        while (nBytesRead != -1) { 
            nBytesRead = audioInputStream.read(abData, 0, abData.length);
            if (nBytesRead >= 0) 
                auline.write(abData, 0, nBytesRead);
        } 
    } catch (IOException e) { 
        e.printStackTrace();
        return;
    } finally { 
        auline.drain();
        auline.close();//closes the file
    } 

} 
} 

I realise it is quite a bit of code to look through but it would really help me a lot to understand this code. I only need help with the AePlayWav class because it is the more complicated class. I have included documentation for what I do understand but do not want to use any code that is above my level of knowledge. Any help in the documentation would help me a lot.

thanks,

Jaro

[NormR1]

Have you read the API doc for the classes and methods that the code uses? Did you have questions about what the doc says?