LocalDateTime

LocalDateTime

• LocalDateTime和DateTimeFormatter都是线程安全的

import java.time.LocalDateTime;
import java.time.Month;
import java.time.format.DateTimeFormatter;

public class Test {
    public static void main(String[] args) throws CloneNotSupportedException {
        // 当前时刻
        LocalDateTime rightNow = LocalDateTime.now();
        rightNow.toString();        // 2021-12-20T19:36:46.199019500
        rightNow.getYear();         // 2021
        rightNow.getMonth();        // DECEMBER
        rightNow.getDayOfYear();    // 354
        rightNow.getDayOfMonth();   // 20
        rightNow.getDayOfWeek();    // MONDAY
        rightNow.getHour();         // 19
        rightNow.getMinute();       // 36
        rightNow.getSecond();       // 46

        // 构造
        LocalDateTime oneDay = LocalDateTime.of(2021, Month.DECEMBER, 20, 19, 38, 0);
        System.out.println(oneDay); // 2021-12-20T19:38

        // 修改日期
        rightNow = oneDay.minusYears(1)
                .plusMonths(2)
                .withDayOfMonth(10)
                .withHour(12);
        System.out.println(rightNow);   // 2021-02-10T12:38

        // 格式化日期
        rightNow.format(DateTimeFormatter.ISO_DATE);    // 2021-02-10
        rightNow.format(DateTimeFormatter.ofPattern("yyyy/MM/dd")); // 2021/02/10

        // 解析
        LocalDateTime.parse("2021/02/10 11:21", DateTimeFormatter.ofPattern("yyyy/MM/dd HH:mm"));   // 2021-02-10T11:21
    }
}