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AudioInputStream 抛出 NullPointerException

如何解决AudioInputStream 抛出 NullPointerException

我一直在寻找一种从我的项目中导出 JAR 文件方法,无论它位于何处,它都能始终播放声音文件。为此,我编写了以下代码,返回文件的确切路径。

public MouseHandler() {
    playSound("rsc/click.wav");
}
public void playSound(final String fileName) {
    File file = new File(fileName);
    try {
        URL fileUrl = file.toURI().toURL();
        String urls = fileUrl.toString();
        urls = urls.replaceFirst("file:/","file:///");
        System.out.println(urls);
        Clip clip = AudioSystem.getClip();
        AudioInputStream inputStream = AudioSystem
                .getAudioInputStream(MouseHandler.class.getResourceAsstream(urls));
        clip.open(inputStream);
        clip.start();
    } catch (Exception e) {
        e.printstacktrace();
    }
}

当我让 AudioInputStream 作为流打开文件时,它会抛出 NullPointerException,即使 URL 之前有一个值。

file:///X:/workspace/eclipse/minesweeper/rsc/click.wav
java.lang.NullPointerException
at java.base/java.util.Objects.requireNonNull(Objects.java:222)
at java.desktop/javax.sound.sampled.AudioSystem.getAudioInputStream(AudioSystem.java:1006)
at configs.MouseHandler.playSound(MouseHandler.java:62)
[AudioInputStream inputStream = AudioSystem
                .getAudioInputStream(MouseHandler.class.getResourceAsstream(urls));]
at configs.MouseHandler.<init>(MouseHandler.java:45)
[playSound("rsc/click.wav");]
at configs.Button.<init>(Button.java:57)
at gui.Frame.<init>(Frame.java:81)
at start.Main.main(Main.java:13)

我知道如果我给 AudioInputStream "rsc/click.wav" 不会发生这种情况,但是当我导出项目时找不到该文件。如果有另一种方法可以导出仍然可以播放音频文件的项目,如果可行,我想使用它。

解决方法

stackoverflow.com/tags/javasound/info 的解决方案对我有用,非常感谢!

public void playSound(final URL fileName) throws Exception {

        new Thread(new Runnable() {
        public void run() {
            try {
                AudioInputStream audioInputStream = AudioSystem.getAudioInputStream(fileName);
                AudioFormat audioFormat = new AudioFormat(Encoding.PCM_SIGNED,44100,16,2,4,false);
                Info info = new DataLine.Info(SourceDataLine.class,audioFormat);
                SourceDataLine sourceDataLine = (SourceDataLine) AudioSystem.getLine(info);
                sourceDataLine.open(audioFormat);
                int bytesRead = 0;
                byte[] buffer = new byte[1024];
                sourceDataLine.start();
                while ((bytesRead = audioInputStream.read(buffer)) != -1) {
                    sourceDataLine.write(buffer,bytesRead);
                }
                sourceDataLine.drain();
                sourceDataLine.stop();
            } catch (Exception e) {
                System.err.println(e.getMessage());
            }
        }
    }).start();
}

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