LocalDateTime一些常用方法及示例

package com.aaa.day04.api;

import com.aaa.utils.MyTool;

import java.time.*;
import java.time.format.DateTimeFormatter;
import java.util.Set;

/**
 * @author ：nie6668888
 * @date ：Created in 2024/11/15 14:22
 * @description：
 * @modified By：
 * @version:
 */
public class MyLocalDateTime {
    public static void main(String[] args) {
       /* //获取系统最新时间
        LocalDateTime now = LocalDateTime.now();
        System.out.println(now);
        //获取当前的时区
        ZoneId zoneId = ZoneId.systemDefault();
        System.out.println(zoneId);
        //获取所有的时区
        Set<String> zoneIds = ZoneId.getAvailableZoneIds();
        for (String id : zoneIds) {
            System.out.println(id);
        }
        //获取今天是当年的第几天
        int dayOfYear = now.getDayOfYear();
        System.out.println(dayOfYear);*/
        //创建一个loacaldatetime类型的数据
       /* LocalDateTime localDateTime =  LocalDateTime.of(2024,11,14,8,20,15);
        System.out.println(localDateTime);
        //使用字符串方式创建localdatetime
        LocalDateTime localDateTime1 = LocalDateTime.parse("2024-11-14T17:30:45");
        System.out.println(localDateTime1);
        //计算两个时间差
        Duration between = Duration.between(localDateTime1, localDateTime);
       *//* long l = between.toDays() / 365;
        System.out.println(l);*//*
        System.out.println(between);*/
        //以固定格式输入时间 yyyy-MM-dd HH:mm:ss，DateTimeFormatter
        //获取一个DateTimeFormatter对象
/*        DateTimeFormatter dtf=DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        LocalDateTime dateTime = LocalDateTime.parse("2024-11-14 17:30:45.345", dtf);
        System.out.println(dateTime);*/
        //使用localdatetime转换成字符串yyyy-MM-dd HH:mm:ss
   /*     LocalDateTime localDateTime = LocalDateTime.now();
        DateTimeFormatter dtf=DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        String format = localDateTime.format(dtf);
        System.out.println(format);*/
  /*      LocalDateTime localDateTime = LocalDateTime.now();
        String s = MyTool.fromLocalDateTimeToString(localDateTime);
        System.out.println(s);*/
       /* LocalTime time= LocalTime.now();
        System.out.println(time);*/
        LocalDate date=LocalDate.now();
        System.out.println(date);
    }
}