When you enable Autoloader , you not need to worry about the incoming files , that when it will come or not , in spark streaming files will be coming continously , but suppose you are not sure about the files that when the fill will be come to the landing to get processed , in that scenario , if you autoloader works

autoloader will send the files automatically to get processed whenever the files comes , if you file have arrived on any particular day , it will automatically send the new files only for the processing .