Sort the dates using library sort function with custom Comparator
Collections . sort ( arr , new Comparator < > ( ) { public int compare ( String date1 , String date2 ) { String day1 = date1 . substring ( 0 , 2 ) ; String month1 = date1 . substring ( 3 , 5 ) ; String year1 = date1 . substring ( 6 ) ; String day2 = date2 . substring ( 0 , 2 ) ; String month2 = date2 . substring ( 3 , 5 ) ; String year2 = date2 . substring ( 6 ) ;