Java_时间与日期（JDK8）

我就是我 2023-02-10 05:21 32阅读 0赞

/**
     * 获取时间戳
     */
    public static void getInstant() {
        
        Instant instant=Instant.now();
        System.out.println(instant.getEpochSecond());
        System.out.println(instant.toEpochMilli());
    }
    
    
    /**
     * 打印昨天当前时刻
     */
    public static void getYesterday() {
        
        LocalDateTime today=LocalDateTime.now();
        LocalDateTime yesterday=today.minusDays(1);
        System.out.println(yesterday);
    }
    
    /**
     * 格式化日期时间
     */
    public static void formatDateTime() {
        
        DateTimeFormatter dateTimeFormatter=DateTimeFormatter.ofPattern("yyyy/MM/dd");
        LocalDate today= LocalDate.now();
        System.out.println(today.format(dateTimeFormatter));
    }
    
    /**
     * 获取当月首末日
     */
    public static void getFistLastOfMonth() {
        
        LocalDate today= LocalDate.now();
        System.out.println(today);
        LocalDate firstDay=LocalDate.of(today.getYear(), today.getMonth(), 1);
        System.out.println(firstDay);
        firstDay=today.with(TemporalAdjusters.firstDayOfMonth());
        System.out.println(firstDay);
        LocalDate lastDay=today.with(TemporalAdjusters.lastDayOfMonth());
        System.out.println(lastDay);
    }
    
    /**
     * 获取1970.1.1 0:0:0至今的毫秒数
     * @return
     */
    public static long getMillis() {
        
        return Clock.systemDefaultZone().millis();
    }
    
    /**
     * 获取当前年月日时分秒
     */
    public static void getDateTime() {
        
        LocalDateTime localDateTime=LocalDateTime.now();
        System.out.println(localDateTime.getYear());
        System.out.println(localDateTime.getMonth()+":"+localDateTime.getMonthValue());
        System.out.println(localDateTime.getDayOfMonth());
        System.out.println(localDateTime.getHour());
        System.out.println(localDateTime.getMinute());
        System.out.println(localDateTime.getSecond());
    }