Use LocalDate
class to parse and generate text in various formats.
DateTimeFormatter in = DateTimeFormatter.ofPattern( "uuuu/MM/dd" ) ;
LocalDate ld = LocalDate.parse( "1998/10/05" , in ) ;
DateTimeFormatter out = DateTimeFormatter.ofPattern( "dd/MM/uuuu" ) ;
String output = ld.format( out ) ;
Tip: Educate the publisher of your data about the ISO 8601 standard for exchanging date-time values textually.