Need a little help with sound in a JApplet

Question

I am working on a solitaire game in Java, and i need to implement sound when the desk is shuffled, card flipped, etc. I used the following sites as reference to try and get it to work, but i am getting Null Pointer Exceptions or mishandled URL exception (depending on what i tweak).
here
Also, i am using netbeans 6.7.1 as my IDE.
I will try to break down the code and explain:

package cardgame;

import java.applet.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JApplet;
import javax.swing.*;
import java.io.*;
import java.net.*;

/**
 *
 * @author jacob
 */
public class Sound extends JApplet {

    private AudioClip song; // Sound player
    private String URL = null;
    private URL songPath; // Sound path
    /*
     *sound_1 =  shuffling cards
     *sound_2 = to discard
     *sound_3 =  from discard
     *sound_4 = cardflip 1
     *sound_5 = cardflip 2
     */

    Sound(String filename) {
        try {
           songPath = new URL(getCodeBase(),filename); // Get the Sound URL
        } catch (MalformedURLException ex) {
            Logger.getLogger(Sound.class.getName()).log(Level.SEVERE, null, ex);
        }
        song = getAudioClip(songPath); // Load the Sound
    }
    Sound(int i) {
        URL = "./sounds/sound_" + i + ".wav";
        System.out.println(URL);
        try {
            songPath = new URL(URL); // Get the Sound URL
            song = getAudioClip(songPath);
        } catch (MalformedURLException ex) {
            Logger.getLogger(Sound.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void playSound() {
        song.loop(); // Play
    }

    public void stopSound() {
        song.stop(); // Stop
    }

    public void playSoundOnce() {
        song.play(); // Play only once
    }
}

    

The 2 different construcors are for different ways i tried to implement this. The first one creates the filepath, and passes it in. The second one builds the filepath in the constructor, given a sound # (i made a list of what numbers correspond to what sound for reference). I am getting the followig errors out:

./sounds/sound_1.wav
Nov 16, 2009 4:14:13 PM cardgame.Sound 
./sounds/sound_2.wav
SEVERE: null
java.net.MalformedURLException: no protocol: ./sounds/sound_1.wav
./sounds/sound_3.wav
        at java.net.URL.(URL.java:583)
        at java.net.URL.(URL.java:480)
        at java.net.URL.(URL.java:429)
./sounds/sound_4.wav
./sounds/sound_5.wav
        at cardgame.Sound.(Sound.java:46)
        at cardgame.Game.loadSounds(Game.java:712)
        at cardgame.Game.(Game.java:62)
        at cardgame.Main.main(Main.java:25)
Nov 16, 2009 4:14:13 PM cardgame.Sound 
SEVERE: null
java.net.MalformedURLException: no protocol: ./sounds/sound_2.wav
        at java.net.URL.(URL.java:583)
        at java.net.URL.(URL.java:480)
        at java.net.URL.(URL.java:429)
        at cardgame.Sound.(Sound.java:46)
        at cardgame.Game.loadSounds(Game.java:712)
        at cardgame.Game.(Game.java:62)
        at cardgame.Main.main(Main.java:25)
Nov 16, 2009 4:14:13 PM cardgame.Sound 
SEVERE: null
java.net.MalformedURLException: no protocol: ./sounds/sound_3.wav
        at java.net.URL.(URL.java:583)
        at java.net.URL.(URL.java:480)
        at java.net.URL.(URL.java:429)
        at cardgame.Sound.(Sound.java:46)
        at cardgame.Game.loadSounds(Game.java:712)
        at cardgame.Game.(Game.java:62)
        at cardgame.Main.main(Main.java:25)
Nov 16, 2009 4:14:13 PM cardgame.Sound 
SEVERE: null
java.net.MalformedURLException: no protocol: ./sounds/sound_4.wav
        at java.net.URL.(URL.java:583)
        at java.net.URL.(URL.java:480)
        at java.net.URL.(URL.java:429)
        at cardgame.Sound.(Sound.java:46)
        at cardgame.Game.loadSounds(Game.java:712)
        at cardgame.Game.(Game.java:62)
        at cardgame.Main.main(Main.java:25)
Nov 16, 2009 4:14:13 PM cardgame.Sound 
SEVERE: null
java.net.MalformedURLException: no protocol: ./sounds/sound_5.wav
        at java.net.URL.(URL.java:583)
        at java.net.URL.(URL.java:480)
        at java.net.URL.(URL.java:429)
        at cardgame.Sound.(Sound.java:46)
        at cardgame.Game.loadSounds(Game.java:712)
        at cardgame.Game.(Game.java:62)
        at cardgame.Main.main(Main.java:25)

    

Thanks for those who read and more thanks to those who help. I know it is somewhat long, but i would rather get it all out there, than have 50 questions that come back or have people not answer due to lack of initial info. also only lets me post a single link right now, so the links are given below

dreamincode.net/forums/showtopic14083.htm
stackoverflow.com/questions/512436/java-playing-wav-sounds
deitel.com/articles/java_tutorials/20060422/LoadingPlayingAudioClips/index.html

Answer 1

According to the stack trace, you are obviously not running the applet in an applet viewer or browser plugin, but instantiating itself through the Main and Game classes. In this case, getCodeBase will return null (it returns the base URL for the Java code, if the applet is actually run as an applet). Hence, the URL class correctly complains when you try to create a URL based on a relative path from an undefined starting point (the result of getCodeBase()).

Answer 2

i guess i should add something to any suggestions on how to implement this as well? i was looking into audiostream class, and using clip.open(var), where var. But is there any suggestions on what to use and how to use it? Those reference sites and either way to undepth or non-informative.