Java8——jdk——java.time包

package com.it.fork;

import java.time.DayOfWeek;
import java.time.Duration;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.OffsetDateTime;
import java.time.Period;
import java.time.ZoneId;
import java.time.ZoneOffset;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.time.temporal.TemporalAdjusters;
import java.util.Set;

import org.junit.Test;

public class TestLocalDateTime {
    
    //6.ZonedDate、ZonedTime、ZonedDateTime ： 带时区的时间或日期
    @Test
    public void test7(){
        LocalDateTime ldt = LocalDateTime.now(ZoneId.of("Asia/Shanghai"));
        System.out.println(ldt); // 2019-12-23T08:59:25.007
        
        ZonedDateTime zdt = ZonedDateTime.now(ZoneId.of("US/Pacific"));
        System.out.println(zdt); // 2019-12-22T16:59:25.009-08:00[US/Pacific]
    }
    
    @Test
    public void test6(){
        Set<String> set = ZoneId.getAvailableZoneIds();
        set.forEach(System.out::println);
    }

    
    //5. DateTimeFormatter : 解析和格式化日期或时间
    @Test
    public void test5(){
//        DateTimeFormatter dtf = DateTimeFormatter.ISO_LOCAL_DATE;
        
        DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy年MM月dd日 HH:mm:ss E");
        
        LocalDateTime ldt = LocalDateTime.now();
        String strDate = ldt.format(dtf);
        
        System.out.println(strDate); // 2019年12月23日 09:00:34 星期一
        
        LocalDateTime newLdt = ldt.parse(strDate, dtf);
        System.out.println(newLdt); // 2019-12-23T09:00:34
    }
    
    //4. TemporalAdjuster : 时间校正器
    @Test
    public void test4(){
    LocalDateTime ldt = LocalDateTime.now();
        System.out.println(ldt); // 2019-12-23T09:02:44.373
        
        LocalDateTime ldt2 = ldt.withDayOfMonth(10);
        System.out.println(ldt2); // 2019-12-10T09:02:44.373
        
        LocalDateTime ldt3 = ldt.with(TemporalAdjusters.next(DayOfWeek.SUNDAY));
        System.out.println(ldt3); // 2019-12-29T09:02:44.373
        
        //自定义：下一个工作日
        LocalDateTime ldt5 = ldt.with((l) -> {
            LocalDateTime ldt4 = (LocalDateTime) l;
            
            DayOfWeek dow = ldt4.getDayOfWeek();
            
            if(dow.equals(DayOfWeek.FRIDAY)){
                return ldt4.plusDays(3);
            }else if(dow.equals(DayOfWeek.SATURDAY)){
                return ldt4.plusDays(2);
            }else{
                return ldt4.plusDays(1);
            }
        });
        
        System.out.println(ldt5); // 2019-12-24T09:02:44.373
        
    }
    
    //3.
    //Duration : 用于计算两个“时间”间隔
    //Period : 用于计算两个“日期”间隔
    @Test
    public void test3(){
        Instant ins1 = Instant.now();
        
        System.out.println("--------------------");
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
        }
        
        Instant ins2 = Instant.now();
        
        System.out.println("所耗费时间为：" + Duration.between(ins1, ins2)); // 所耗费时间为：PT1.016S
        
        System.out.println("----------------------------------");
        
        LocalDate ld1 = LocalDate.now();
        LocalDate ld2 = LocalDate.of(2011, 1, 1);
        
        Period pe = Period.between(ld2, ld1);
        System.out.println(pe.getYears()); // 8
        System.out.println(pe.getMonths()); // 11
        System.out.println(pe.getDays()); // 22
    }
    
    //2. Instant : 时间戳。 （使用 Unix 元年  1970年1月1日 00:00:00 所经历的毫秒值）
    @Test
    public void test2(){
        Instant ins = Instant.now();  //默认使用 UTC 时区
        System.out.println(ins); // 2019-12-23T01:05:16.251Z
        
        OffsetDateTime odt = ins.atOffset(ZoneOffset.ofHours(8));
        System.out.println(odt); // 2019-12-23T09:05:16.251+08:00
        
        System.out.println(ins.getNano()); // 251000000
        
        Instant ins2 = Instant.ofEpochSecond(5);
        System.out.println(ins2); // 1970-01-01T00:00:05Z
    }
    
    //1. LocalDate、LocalTime、LocalDateTime
    @Test
    public void test1(){
        LocalDateTime ldt = LocalDateTime.now();
        System.out.println(ldt); // 2019-12-23T09:06:27.334
        
        LocalDateTime ld2 = LocalDateTime.of(2016, 11, 21, 10, 10, 10);
        System.out.println(ld2); // 2016-11-21T10:10:10
        
        LocalDateTime ldt3 = ld2.plusYears(20);
        System.out.println(ldt3); // 2036-11-21T10:10:10
        
        LocalDateTime ldt4 = ld2.minusMonths(2);
        System.out.println(ldt4); // 2016-09-21T10:10:10
        
        System.out.println(ldt.getYear()); // 2019
        System.out.println(ldt.getMonthValue()); // 12
        System.out.println(ldt.getDayOfMonth()); // 23
        System.out.println(ldt.getHour()); // 9
        System.out.println(ldt.getMinute()); // 6
        System.out.println(ldt.getSecond()); // 27
    }

}