java.io.FileNotFoundException: No content provider: http

首先这个问题无法修复。
使用MediaPlayer的时候播放网络音频出现了以下错误，记录如下：
原代码:

    /**
     * 播放音频文件
     */
    private void playVoice(String voicePath){
        MediaPlayer player = MediaPlayer.create(context, Uri.parse(voicePath));
        player.start();
    }

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错误日志：

W/MediaPlayer: Couldn't open https://dq-oss.oss-cn-beijing.aliyuncs.com/...
    java.io.FileNotFoundException: No content provider: https://dq-oss.oss-cn-beijing.aliyuncs.com/audio_recordrecord_20200414_14_32_58.mp3
        at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1688)
        at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1518)
        at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1435)
        at android.media.MediaPlayer.attemptDataSource(MediaPlayer.java:1154)
        at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1112)
        at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1019)
        at android.media.MediaPlayer.create(MediaPlayer.java:926)
        at android.media.MediaPlayer.create(MediaPlayer.java:903)
        at android.media.MediaPlayer.create(MediaPlayer.java:882)
        at com.example.qcsdk.adapter.ChatP2PAdapter.playVoice(ChatP2PAdapter.java:255)
        at com.example.qcsdk.adapter.ChatP2PAdapter.access$000(ChatP2PAdapter.java:40)
        at com.example.qcsdk.adapter.ChatP2PAdapter$2.onClick(ChatP2PAdapter.java:222)
        at android.view.View.performClick(View.java:7161)
        at android.view.View.performClickInternal(View.java:7138)
        at android.view.View.access$3500(View.java:811)
        at android.view.View$PerformClick.run(View.java:27419)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:224)
        at android.app.ActivityThread.main(ActivityThread.java:7520)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
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这个错误是在小米上，虽然报错了但是还是会有声音，不过为了防止出现其他问题，还是进行了修复，修改后的代码如下：

    /**
     * 播放音频文件
     */
    private void playVoice(String voicePath){
//        MediaPlayer player = MediaPlayer.create(context, Uri.parse(voicePath));
        MediaPlayer player = new MediaPlayer();
        try {
            player.setDataSource(voicePath);
        }catch (IOException e){
            e.printStackTrace();
        }
        player.prepareAsync();
        player.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mediaPlayer) {
                mediaPlayer.start();
            }
        });
    }
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这个问题的原因是因为 Uri.parse(voicePath)把网络路径转换成了本地路径，这时候本地没有这个文件才出现这个问题，比如上述的https://dq-oss.oss-cn-beijing.aliyuncs.com/audio_recordrecord_20200414_14_32_58.mp3使用 Uri.parse(voicePath)转换为路径后结果为/audio_recordrecord_20200414_14_32_58.mp3，这样当然不能播放，不过有的手机即使报错了依然可以播放，还不知道是为什么。不过按照Android源码来看的话，是绝对会报错的。下面解释源码的问题。

问题主要出在MediaPlayer上面，当使用Mediaplayer执行setDataSource(@NonNull Context context, @NonNull Uri uri)函数时候，最终会执行到

setDataSource(@NonNull Context context, @NonNull Uri uri,
            @Nullable Map<String, String> headers, @Nullable List<HttpCookie> cookies)
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里面，这里我们看下这个函数的代码：
MediaPlayer.java

/**
     * Sets the data source as a content Uri.
     *
     * To provide cookies for the subsequent HTTP requests, you can install your own default cookie
     * handler and use other variants of setDataSource APIs instead. Alternatively, you can use
     * this API to pass the cookies as a list of HttpCookie. If the app has not installed
     * a CookieHandler already, this API creates a CookieManager and populates its CookieStore with
     * the provided cookies. If the app has installed its own handler already, this API requires the
     * handler to be of CookieManager type such that the API can update the manager’s CookieStore.
     *
     * <p><strong>Note</strong> that the cross domain redirection is allowed by default,
     * but that can be changed with key/value pairs through the headers parameter with
     * "android-allow-cross-domain-redirect" as the key and "0" or "1" as the value to
     * disallow or allow cross domain redirection.
     *
     * @param context the Context to use when resolving the Uri
     * @param uri the Content URI of the data you want to play
     * @param headers the headers to be sent together with the request for the data
     *                The headers must not include cookies. Instead, use the cookies param.
     * @param cookies the cookies to be sent together with the request
     * @throws IllegalArgumentException if cookies are provided and the installed handler is not
     *                                  a CookieManager
     * @throws IllegalStateException    if it is called in an invalid state
     * @throws NullPointerException     if context or uri is null
     * @throws IOException              if uri has a file scheme and an I/O error occurs
     */
    public void setDataSource(@NonNull Context context, @NonNull Uri uri,
            @Nullable Map<String, String> headers, @Nullable List<HttpCookie> cookies)
            throws IOException {
        if (context == null) {
            throw new NullPointerException("context param can not be null.");
        }

        if (uri == null) {
            throw new NullPointerException("uri param can not be null.");
        }

        if (cookies != null) {
            CookieHandler cookieHandler = CookieHandler.getDefault();
            if (cookieHandler != null && !(cookieHandler instanceof CookieManager)) {
                throw new IllegalArgumentException("The cookie handler has to be of CookieManager "
                        + "type when cookies are provided.");
            }
        }

        // The context and URI usually belong to the calling user. Get a resolver for that user
        // and strip out the userId from the URI if present.
        final ContentResolver resolver = context.getContentResolver();
        final String scheme = uri.getScheme();
        final String authority = ContentProvider.getAuthorityWithoutUserId(uri.getAuthority());
        if (ContentResolver.SCHEME_FILE.equals(scheme)) {
            setDataSource(uri.getPath());
            return;
        } else if (ContentResolver.SCHEME_CONTENT.equals(scheme)
                && Settings.AUTHORITY.equals(authority)) {
            // Try cached ringtone first since the actual provider may not be
            // encryption aware, or it may be stored on CE media storage
            final int type = RingtoneManager.getDefaultType(uri);
            final Uri cacheUri = RingtoneManager.getCacheForType(type, context.getUserId());
            final Uri actualUri = RingtoneManager.getActualDefaultRingtoneUri(context, type);
            if (attemptDataSource(resolver, cacheUri)) {
                return;
            } else if (attemptDataSource(resolver, actualUri)) {
                return;
            } else {
                setDataSource(uri.toString(), headers, cookies);
            }
        } else {
            // Try requested Uri locally first, or fallback to media server
            if (attemptDataSource(resolver, uri)) {
                return;
            } else {
                setDataSource(uri.toString(), headers, cookies);
            }
        }
    }
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因为路径是网络链接，以http或者https开头，所以会执行到最后的else代码块中，然后会执行到 attemptDataSource(ContentResolver resolver, Uri uri)函数，下面看下这个函数：
MediaPlayer.java

    private boolean attemptDataSource(ContentResolver resolver, Uri uri) {
        try (AssetFileDescriptor afd = resolver.openAssetFileDescriptor(uri, "r")) {
            setDataSource(afd);
            return true;
        } catch (NullPointerException | SecurityException | IOException ex) {
            Log.w(TAG, "Couldn't open " + (uri == null ? "null uri" : uri.toSafeString()), ex);
            return false;
        }
    }
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可以看到第一行代码是用来判断Asset的资源文件，这时候就会出现报错，因为我们的资源是网络资源…
暂时不知道怎么解决这个事情，等Android更新吧…

想验证这个问题的话把try里面的代码

AssetFileDescriptor afd = resolver.openAssetFileDescriptor(uri, "r")
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复制出来测试下就行了