[Java] 11.1.3. JRE 라이브러리 import - LocalDate

1. LocalDate & LocalDateTime

2. LocalDate 사용 예제

package ex08;

import java.time.LocalDate;
import java.time.LocalTime;

public class LDate01 {
    public static void main(String[] args) {
        // 1. 현재 날짜
        LocalDate nowDate = LocalDate.now();
        System.out.println(nowDate);

        // 2. 현재 시간
        LocalTime nowTime = LocalTime.now();
        System.out.println(nowTime);

        // 3. 날짜 더하기/빼기
        LocalDate plusDays = nowDate.plusDays(20);
        System.out.println(plusDays);

        // 4. 주 더하기/빼기
        LocalDate plusWeeks = nowDate.plusWeeks(3);
        System.out.println(plusWeeks);

        // 5. 월 더하기/빼기
        LocalDate plusMonths = nowDate.plusMonths(11);
        System.out.println(plusMonths);

        // 6. 현재날짜의 연도, 월, 요일 확인하기
        System.out.println(nowDate.getYear());
        System.out.println(nowDate.getMonth());
        System.out.println(nowDate.getDayOfMonth());
    }
}

3. ChronoUnit

package ex08;

import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class Chrono01 {
    public static void main(String[] args) {
        LocalDateTime writeTime = LocalDateTime.of(2025, 02, 11, 10, 3);
        LocalDateTime nowTime = LocalDateTime.now();

        long daysBetween = ChronoUnit.DAYS.between(nowTime, writeTime);
        long hoursBetween = ChronoUnit.HOURS.between(nowTime, writeTime);
        long minsBetween = ChronoUnit.MINUTES.between(nowTime, writeTime);

        System.out.println(daysBetween + "일전");
        System.out.println(hoursBetween + "시간전");
        System.out.println(minsBetween + "분전");
    }
}