question: @ Override public String resolveVideoUrl ( @ Nullable final Video video , Step step ) { if ( video == null ) return null ; String localPath = databaseFacade . getPathToVideoIfExist ( video ) ; if ( localPath != null && checkExistingOnDisk ( localPath , step ) ) { return localPath ; } else { List < VideoUrl > urlList = video . getUrls ( ) ; if ( urlList == null || urlList . size ( ) == 0 ) return null ; return resolveFromWeb ( urlList ) ; } }
target:  Don't call in main thread