java8新特性_20_时间格式化与时区处理

@Test
    public void test2(){
        DateTimeFormatter dtf = DateTimeFormatter.ISO_DATE;
        LocalDateTime ldt = LocalDateTime.now();

        String strDate = ldt.format(dtf);
        System.out.println(strDate);//2019-09-27

        DateTimeFormatter dtf2 = DateTimeFormatter.ISO_DATE_TIME;
        System.out.println(ldt.format(dtf2));//2019-09-27T08:34:51.378

        DateTimeFormatter dtf3 = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        String strDate2 = ldt.format(dtf3);
        System.out.println(strDate2);//2019-09-27 08:34:51

        LocalDateTime newDate = LocalDateTime.parse(strDate2, dtf3);
        System.out.println(newDate);//2019-09-27T08:38:09
    }

//支持的时区
    @Test
    public void test3(){
        Set<String> availableZoneIds = ZoneId.getAvailableZoneIds();
        availableZoneIds.forEach(System.out::println);
    }

    //带时区的时间
    @Test
    public void test4(){
        LocalDateTime ldt = LocalDateTime.now(ZoneId.of("Europe/Tallinn"));
        System.out.println(ldt);

        LocalDateTime localDateTime = LocalDateTime.now(ZoneId.of("Europe/Tallinn"));
        ZonedDateTime zdt = localDateTime.atZone(ZoneId.of("Europe/Tallinn"));
        System.out.println(zdt);
    }