JAVA---jdk8中日期类

package java0;

import org.junit.Test;
import sun.plugin.dom.exception.InvalidStateException;

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

/**
 *
 *
 *
 * @create 2022-03-23 10:43
 */
public class JDK8DateTimeTest {
    /*
        LocalDate、LocalTime、LocalDateTime 的使用

     */

    @Test
    public void test1(){
        //now():获取当前的日期、时间、日期+时间
        LocalDate localDate=LocalDate.now();
        LocalTime localTime=LocalTime.now();
        LocalDateTime localDateTime=LocalDateTime.now();

        System.out.println(localDate);
        System.out.println(localTime);
        System.out.println(localDateTime);


        //of():设置指定的年月日时分秒，没有偏移量
        LocalDateTime localDateTime1=LocalDateTime.of(2022,3,23,10,50,1);
        System.out.println(localDateTime1);


        //getXxx():获取相关的属性
        System.out.println(localDateTime.getDayOfMonth());
        System.out.println(localDateTime.getDayOfWeek());
        System.out.println(localDateTime.getMonth());
        System.out.println(localDateTime.getMonthValue());
        System.out.println(localDateTime.getMinute());


        //withXxx():设置相关的属性
        LocalDate localDate1=localDate.withDayOfMonth(11);
        System.out.println(localDate);
        System.out.println(localDate1);




    }

    @Test
    public void test2(){
        //now()获取本初子午线对应的标准时间
        Instant instant=Instant.now();
        System.out.println(instant);

        //添加时间的偏移量
        OffsetDateTime offsetDateTime=instant.atOffset(ZoneOffset.ofHours(8));
        System.out.println(offsetDateTime);

        //toEpochMilli():获取自1970年1月1日0时0分0秒（UTC）开始的毫秒数 --》Date类的getTime()
        long milli= instant.toEpochMilli();
        System.out.println(milli);

        //通过给定的毫秒数，获取instant实例
        Instant instant1=Instant.ofEpochMilli(213423424234L);
        System.out.println(instant1);

    }

    /*

            DateTimeFormatter:格式化或解析日期、时间

     */

    @Test
    public void test3(){
        DateTimeFormatter formatter=DateTimeFormatter.ISO_LOCAL_DATE_TIME;
        LocalDateTime localDateTime=LocalDateTime.now();
        String str1=formatter.format(localDateTime);
        System.out.println(localDateTime);
        System.out.println(str1);
        
        
    }
}