question: public void playFileForUser ( String fileName , String userName ) throws SoundPlaybackException { if ( userName == null || userName . isEmpty ( ) ) { userName = appProperties . getProperty ( "username_to_join_channel" ) ; } try { Guild guild = getUsersGuild ( userName ) ; joinUsersCurrentChannel ( userName ) ; playFile ( fileName , guild ) ; } catch ( Exception e ) { e . printStackTrace ( ) ; } }
target:  Joins the channel of the user provided and then plays a file.