Play mp3 files in java - nullpointerexception

Question

I'm creating an app with some background music. I am trying to play that music with this class:

import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.Clip;

public class SoundPlayer {

    public static void playSound() {
        try{
              AudioInputStream audioInputStream = AudioSystem.getAudioInputStream(SoundPlayer.class.getResource("/Music.mp3"));
             Clip clip = AudioSystem.getClip();
             clip.open(audioInputStream);
             clip.start( );
            }
           catch(Exception ex) {
               ex.printStackTrace();
           }

    }
}

But I get a nullpointerexception on line 9 which is the AudioInputStream. I don't know how I can access this file:

I tried:

SoundPlayer.class.getResource("/Music.mp3")
SoundPlayer.class.getResource("Music/Music.mp3")
SoundPlayer.class.getResource("./Music/Music.mp3")

When I put it in the root of my files and use this:

SoundPlayer.class.getResource("Music.mp3")

I get this error: javax.sound.sampled.UnsupportedAudioFileException: could not get audio input stream from input URL Update I tried it to do with JavaFX:

package com.audio;

import java.nio.file.Paths;

import javafx.scene.media.Media;
import javafx.scene.media.MediaPlayer;

public class PlayAudio {

    public static void PlayMP3() {
        Media media = new Media(Paths.get("Music/Music.mp3").toUri().toString());
        MediaPlayer player = new MediaPlayer(media);
        player.play();
    }
}

but I get the error:

Exception in thread "Thread-2" java.lang.IllegalStateException: Toolkit not initialized
    at com.sun.javafx.application.PlatformImpl.runLater(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.runLater(Unknown Source)
    at javafx.application.Platform.runLater(Unknown Source)
    at javafx.scene.media.Media$_MetadataListener.onMetadata(Unknown Source)
    at com.sun.media.jfxmediaimpl.MetadataParserImpl.done(Unknown Source)
    at com.sun.media.jfxmediaimpl.platform.java.ID3MetadataParser.parse(Unknown Source)
    at com.sun.media.jfxmediaimpl.MetadataParserImpl.run(Unknown Source)
Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: Toolkit not initialized
    at com.sun.javafx.application.PlatformImpl.runLater(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.runLater(Unknown Source)
    at javafx.application.Platform.runLater(Unknown Source)
    at javafx.scene.media.MediaPlayer.init(Unknown Source)
    at javafx.scene.media.MediaPlayer.<init>(Unknown Source)
    at com.audio.PlayAudio.PlayMP3(PlayAudio.java:12)
    at com.Frame1$2.actionPerformed(Frame1.java:61)
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
    at java.awt.Component.processMouseEvent(Unknown Source)

The error in on this line: MediaPlayer player = new MediaPlayer(media); How can I initialize the toolkit?

Did you check if your folder and file exist in the .jar-file? — Yannick Rot, Dec 06 '15 at 13:14

Benjamin Owen · Accepted Answer · 2015-12-06T14:34:47.163

2

Try putting the file in the root directory. Maybe you can access it from there, using MainClass.getResourceAsStream("file.mp3");

EDIT: Use .wav files.

edited Dec 06 '15 at 14:34

answered Dec 06 '15 at 13:14

Benjamin Owen

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2
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I put it in the root and got this error:could not get audio input stream from input URL – RuuddR Dec 06 '15 at 13:16
Are you using `getResourceAsStream()`? That might give you the `InputStream` you need. – Benjamin Owen Dec 06 '15 at 13:17
You are also getting an `UnsupportedAudioFileException` . Have you tried different audio formats? – Benjamin Owen Dec 06 '15 at 13:18
No, I didn't try different audio formats, but is there a way to use mp3? That's the most used format in my eyes. – RuuddR Dec 06 '15 at 13:19
The getResourceAsStream doesn't make any difference. – RuuddR Dec 06 '15 at 13:22
Look at the link I gave you. – Benjamin Owen Dec 06 '15 at 13:23
I looked at it, but I can't really get something out of it. I don't understand that. I am not really good with java. – RuuddR Dec 06 '15 at 13:24
I would suggest downloading some of the example files there, decompiling them, and looking at the code and jar file structure. – Benjamin Owen Dec 06 '15 at 13:25
I don't see any example file? – RuuddR Dec 06 '15 at 13:27
Sorry, you should read through this page. If you still don't get it, read through the entire section. https://docs.oracle.com/javase/tutorial/sound/accessing.html – Benjamin Owen Dec 06 '15 at 13:29
I am now going to try to do it with JavaFX, but I get Exception in thread "Thread-2" java.lang.IllegalStateException: Toolkit not initialized – RuuddR Dec 06 '15 at 13:53
Initialize the Toolkit variable, I'd assume. – Benjamin Owen Dec 06 '15 at 13:54
But how would I do that? I have added the class I am using. – RuuddR Dec 06 '15 at 13:56
It's in the main post. – RuuddR Dec 06 '15 at 13:57
MediaPlayer player = new MediaPlayer(media); – RuuddR Dec 06 '15 at 13:59
I'll just use wav files for this :P – RuuddR Dec 06 '15 at 14:32
You'd think Java would have better APIs for this. – Benjamin Owen Dec 06 '15 at 14:33
Yeh, indeed. This sucks a bit. – RuuddR Dec 06 '15 at 14:34
Accepted your answer. – RuuddR Dec 06 '15 at 14:35
http://stackoverflow.com/questions/3125934/lineunavailableexception-for-playing-mp3-with-java/3126243#3126243 – Romain Hippeau May 18 '17 at 20:03

Play mp3 files in java - nullpointerexception

1 Answers1