播放libview生成的视频URL时，ExoPlayer 404错误

Question

我正在使用libview库使用ExoPlayer播放加密的视频。问题是当我尝试播放库生成的URL时，ExoPlayer抛出404错误。

com.google.android.exoplayer2.upstream.HttpDataSource$InvalidResponseCodeException: Response code: 404
            at com.google.android.exoplayer2.upstream.DefaultHttpDataSource.open(DefaultHttpDataSource.java:211)
            at com.google.android.exoplayer2.upstream.DefaultDataSource.open(DefaultDataSource.java:147)
            at com.google.android.exoplayer2.source.ExtractorMediaPeriod$ExtractingLoadable.load(ExtractorMediaPeriod.java:841)
            at com.google.android.exoplayer2.upstream.Loader$LoadTask.run(Loader.java:308)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
            at java.lang.Thread.run(Thread.java:761)