Program: 170836
Project: 170836
Buggy source:
@Override public void loadLrc(SongEntity entity){
  LrcUseCase.Param param=new LrcUseCase.Param(entity.title,"String_Node_Str");
  String fileName=entity.title + "String_Node_Str" + entity.artistName+ "String_Node_Str";
  File lrcFile=new File(FileManager.getInstance().getLrcDir().getAbsolutePath(),fileName);
  Observable.just(lrcFile).flatMap(file -> {
    if (file.exists() && file.canRead()) {
      return Observable.just(file);
    }
    if (entity.type.equals(BaseDb.QueueParam.LOCAL)) {
      return mLrcUseCase.buildObservable(param).flatMap(responseBody -> {
        boolean saveFile=FileManager.getInstance().saveFile(responseBody.byteStream(),fileName);
        return saveFile ? Observable.just(file) : null;
      }
);
    }
 else {
      return mLrcUseCase.getBaiduLrcData(NetConstants.Value.METHOD_LRC,entity.id).flatMap(s -> {
        boolean saveFile=FileManager.getInstance().saveFile(new ByteArrayInputStream(s.getBytes("String_Node_Str")),fileName);
        return saveFile ? Observable.just(file) : null;
      }
);
    }
  }
).map((Function<File,List<Lrc>>)file -> {
    if (file == null || !file.exists()) {
      return Collections.emptyList();
    }
    return LrcHelper.parseLrcFromFile(file);
  }
).compose(RxHelper.ioMain()).subscribeWith(new DefaultDisposableObserver<List<Lrc>>(){
    @Override protected void onStart(){
      super.onStart();
      if (getView() == null) {
        return;
      }
      getView().startDownloadLrc();
    }
    @Override public void onNext(    List<Lrc> lrcs){
      super.onNext(lrcs);
      if (getView() == null) {
        return;
      }
      getView().downloadLrcSuccess(lrcs);
    }
    @Override public void onError(    Throwable e){
      super.onError(e);
      if (getView() == null) {
        return;
      }
      getView().downloadFailed(e);
    }
  }
);
}

Fixed version (ground truth):
@Override public void loadLrc(SongEntity entity){
  LrcUseCase.Param param=new LrcUseCase.Param(entity.title,"String_Node_Str");
  String fileName=entity.title + "String_Node_Str" + entity.artistName+ "String_Node_Str";
  File lrcFile=new File(FileManager.getInstance().getLrcDir().getAbsolutePath(),fileName);
  Observable.just(lrcFile).flatMap(file -> {
    if (file.exists() && file.canRead()) {
      return Observable.just(file);
    }
    if (entity.type.equals(BaseDb.QueueParam.LOCAL)) {
      LogUtil.i(TAG,"String_Node_Str");
      return mLrcUseCase.buildObservable(param).flatMap(responseBody -> {
        boolean saveFile=FileManager.getInstance().saveFile(responseBody.byteStream(),fileName);
        return saveFile ? Observable.just(file) : null;
      }
);
    }
 else {
      LogUtil.i(TAG,"String_Node_Str");
      return mLrcUseCase.getBaiduLrcData(NetConstants.Value.METHOD_LRC,entity.id).flatMap(s -> {
        boolean saveFile=FileManager.getInstance().saveFile(new ByteArrayInputStream(s.getBytes("String_Node_Str")),fileName);
        return saveFile ? Observable.just(file) : null;
      }
);
    }
  }
).map((Function<File,List<Lrc>>)file -> {
    if (file == null || !file.exists()) {
      return Collections.emptyList();
    }
    return LrcHelper.parseLrcFromFile(file);
  }
).compose(RxHelper.ioMain()).subscribeWith(new DefaultDisposableObserver<List<Lrc>>(){
    @Override protected void onStart(){
      super.onStart();
      if (getView() == null) {
        return;
      }
      getView().startDownloadLrc();
    }
    @Override public void onNext(    List<Lrc> lrcs){
      super.onNext(lrcs);
      if (getView() == null) {
        return;
      }
      getView().downloadLrcSuccess(lrcs);
    }
    @Override public void onError(    Throwable e){
      super.onError(e);
      if (getView() == null) {
        return;
      }
      getView().downloadFailed(e);
    }
  }
);
}