Java List to Map

 Set<String> oids = attendanceListResponseBodyDTOS.stream().map(o -> o.getOid()).collect(Collectors.toSet());

List<AttendanceDTO> resultDB = attendanceService.convertForRead(

attendanceService.getRepository().findByOidInAndIsDeleted(oids,Api.NO)

);

Map<String, AttendanceDTO> attendanceDTOMap = resultDB.stream().collect(

Collectors.toMap(AttendanceDTO::getOid, att -> att)

);

Java List interface sort

Sort by created date ascending

List<UniversalShiftDTO> result1 = new ArrayList<>();

result1.sort(Comparator.comparing(UniversalShiftDTO::getCreatedOn));

Sort by created date descending

List<UniversalShiftDTO> result1 = new ArrayList<>();

result1.sort(Comparator.comparing(UniversalShiftDTO::getCreatedOn).reversed());

Java 8

Return new list sorted by created date ascending

List<UniversalShiftDTO> result1 = new ArrayList<>();

result1 = result1.stream().sorted(Comparator.comparing(UniversalShiftDTO::getCreatedOn)).collect(Collectors.toList());

Return new list sorted by created date descending

List<UniversalShiftDTO> result1 = new ArrayList<>();

result1 = result1.stream().sorted(Comparator.comparing(UniversalShiftDTO::getCreatedOn).reversed()).collect(Collectors.toList());