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我已经从服务器下载文件并使用jetpack安全文件加密保存，加密和解密对于图像文件工作正常，但对于音频文件，我能够通过解密获得字节数组，但我无法使用exoplayer播放它。

加密类

public class MyEncryption {
Context context;
MasterKey mainKey;

public MyEncryption(Context context) {
    this.context = context;
    try {
        mainKey = new MasterKey.Builder(context)
                .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
                .build();
    } catch (GeneralSecurityException | IOException e) {
        e.printStackTrace();
    }
}

public void encryptFile(final Context context, final File target) throws GeneralSecurityException, IOException {

    int size = (int) target.length();
    byte[] bytes = new byte[size];
    try {
        BufferedInputStream buf = new BufferedInputStream(new FileInputStream(target));
        buf.read(bytes, 0, bytes.length);
        buf.close();
        final EncryptedFile file = new EncryptedFile.Builder(context,
                new File(target.getAbsolutePath()), mainKey, EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB)
                .build();
        target.delete();
        final OutputStream stream = file.openFileOutput();
        stream.write(bytes);
        stream.flush();
        stream.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public byte[] decryptFile(File file) throws GeneralSecurityException, IOException {
    EncryptedFile encryptedFile = new EncryptedFile.Builder(context,
            file,
            mainKey,
            EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB
    ).build();

    InputStream inputStream = encryptedFile.openFileInput();
    ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
    int nextByte = inputStream.read();
    while (nextByte != -1) {
        byteArrayOutputStream.write(nextByte);
        nextByte = inputStream.read();
    }

    byte[] plaintext = byteArrayOutputStream.toByteArray();
    return plaintext;
}

public Bitmap decryptImage(File file) throws GeneralSecurityException, IOException {
    EncryptedFile encryptedFile = new EncryptedFile.Builder(context,
            file,
            mainKey,
            EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB
    ).build();

    InputStream inputStream = encryptedFile.openFileInput();
    return BitmapFactory.decodeStream(inputStream);
}
}

我尝试通过以下方式播放音频：

 private void prepareExoPlayerFromByteArray(byte[] data) {
    TrackSelector trackSelector = new DefaultTrackSelector(getContext());
    LoadControl loadControl = new DefaultLoadControl();
    exoPlayer = new SimpleExoPlayer.Builder(getContext()).setTrackSelector(trackSelector).setLoadControl(loadControl).build();
    exoPlayer.addListener(eventListener);

    final MByteArrayDataSource byteArrayDataSource = new MByteArrayDataSource(data);
    Log.i(TAG, "ByteArrayDataSource constructed.");
    Log.d(TAG, "prepareExoPlayerFromByteArray: " + byteArrayDataSource.getUri());

    DataSource.Factory factory = () -> byteArrayDataSource;
    Log.i(TAG, "DataSource.Factory constructed.");

    MediaSource audioSource = new ProgressiveMediaSource.Factory(factory).createMediaSource(byteArrayDataSource.getUri());
    Log.i(TAG, "Audio source constructed.");
    exoPlayer.prepare(audioSource);
}

此代码不播放音频，它说

    2021-03-31 08:35:16.881 4261-4779/com.xxx.xxx E/LoadTask: Unexpected exception loading stream
    java.lang.NullPointerException
        at com.google.android.exoplayer2.util.Assertions.checkNotNull(Assertions.java:147)
        at com.google.android.exoplayer2.upstream.StatsDataSource.open(StatsDataSource.java:84)
        at com.google.android.exoplayer2.source.ProgressiveMediaPeriod$ExtractingLoadable.load(ProgressiveMediaPeriod.java:961)
        at com.google.android.exoplayer2.upstream.Loader$LoadTask.run(Loader.java:391)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
        at java.lang.Thread.run(Thread.java:919)
2021-03-31 08:35:16.890 4261-4778/com.bipin.koreanvasa E/ExoPlayerImplInternal: Source error.
    com.google.android.exoplayer2.upstream.Loader$UnexpectedLoaderException: Unexpected NullPointerException: null
        at com.google.android.exoplayer2.upstream.Loader$LoadTask.run(Loader.java:413)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
        at java.lang.Thread.run(Thread.java:919)
     Caused by: java.lang.NullPointerException
        at com.google.android.exoplayer2.util.Assertions.checkNotNull(Assertions.java:147)
        at com.google.android.exoplayer2.upstream.StatsDataSource.open(StatsDataSource.java:84)
        at com.google.android.exoplayer2.source.ProgressiveMediaPeriod$ExtractingLoadable.load(ProgressiveMediaPeriod.java:961)
        at com.google.android.exoplayer2.upstream.Loader$LoadTask.run(Loader.java:391)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167) 
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641) 
        at java.lang.Thread.run(Thread.java:919) 

他们有什么办法解决这个问题吗，我参考了Link

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