对当前时间格式化：

     public static long getCurrentTimeMillis(String pattern) {

        return Long.valueOf(toString(LocalDateTime.now(), pattern));

     }

     对指定日期进行格式化：

     public static LocalDate toLocalDate(String date, String pattern) {

        return LocalDate.parse(date, DateTimeFormatter.ofPattern(pattern));

     }

    public static String toString(LocalDate date, String pattern) {

       return date.format(DateTimeFormatter.ofPattern(pattern));

    }

    // 计算偏移日期

    public static LocalDate getOffsetLocalDate(LocalDate targetDate, ChronoUnit unit, long number) {

        return targetDate.plus(number, unit);

    }

    // 获取周一

    public static LocalDate getFirstDayOfWeek(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.previousOrSame(DayOfWeek.MONDAY));

    }

    // 获取周日

    public static LocalDate getLastDayOfWeek(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.nextOrSame(DayOfWeek.SUNDAY));

    }

    // 获取月初

    public static LocalDate getFirstDayOfMonth(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.firstDayOfMonth());

    }

    // 获取月末

    public static LocalDate getLastDayOfMonth(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.lastDayOfMonth());

    }

    // 获取季初

    public static LocalDate getFirstDayOfQuarter(LocalDate localDate) {

        int month = localDate.getMonthValue();

        if (month >= 1 && month <= 3) {

            return LocalDate.of(localDate.getYear(), 1, 1);

        } else if (month >= 4 && month <= 6) {

            return LocalDate.of(localDate.getYear(), 4, 1);

        } else if (month >= 7 && month <= 9) {

            return LocalDate.of(localDate.getYear(), 7, 1);

        } else {

            return LocalDate.of(localDate.getYear(), 10, 1);

        }

    }

    // 获取季末

    public static LocalDate getLastDayOfQuarter(LocalDate localDate) {

        int month = localDate.getMonthValue();

        if (month >= 1 && month <= 3) {

            return LocalDate.of(localDate.getYear(), 3, 31);

        } else if (month >= 4 && month <= 6) {

            return LocalDate.of(localDate.getYear(), 6, 30);

        } else if (month >= 7 && month <= 9) {

            return LocalDate.of(localDate.getYear(), 9, 30);

        } else {

            return LocalDate.of(localDate.getYear(), 12, 31);

        }

    }

    // 获取半年初

    public static LocalDate getFirstDayOfHalfYear(LocalDate localDate) {

        int month = localDate.getMonthValue();

        if (month >= 1 && month <= 6) {

            return LocalDate.of(localDate.getYear(), 1, 1);

        } else {

            return LocalDate.of(localDate.getYear(), 7, 1);

        }

    }

    // 获取半年末

    public static LocalDate getLastDayOfHalfYear(LocalDate localDate) {

        int month = localDate.getMonthValue();

        if (month >= 1 && month <= 6) {

            return LocalDate.of(localDate.getYear(), 6, 30);

        } else {

            return LocalDate.of(localDate.getYear(), 12, 31);

        }

    }

    // 获取年初

    public static LocalDate getFirstDayOfYear(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.firstDayOfYear());

    }

    // 获取年末

    public static LocalDate getLastDayOfYear(LocalDate localDate) {

        return localDate.with(TemporalAdjusters.lastDayOfYear());

    }

    // 计算两个日期相差天数

    public static long getIntervalDays(LocalDate localDate1, LocalDate localDate2) {

        return Math.abs(localDate1.toEpochDay() - localDate2.toEpochDay());

    }