转换时间的工具类(1)

　　

/**
 * Date 转为LocalDateTime
 *
 * @param date
 * @return
 */
public static LocalDateTime convertDateToLDT(Date date) {
    return LocalDateTime.ofInstant(date.toInstant(), ZoneId.systemDefault());
}

/**
 * LocalDateTime转换为Date
 *
 * @param time
 * @return
 */
public static Date convertLDTToDate(LocalDateTime time) {
    return Date.from(time.atZone(ZoneId.systemDefault()).toInstant());
}

/**
 * 获取指定日期的毫秒
 *
 * @param time
 * @return
 */
public static Long getMilliByTime(LocalDateTime time) {
    return time.atZone(ZoneId.systemDefault()).toInstant().toEpochMilli();
}

/**
 * 获取指定日期的秒
 *
 * @param time
 * @return
 */
public static Long getSecondsByTime(LocalDateTime time) {
    return time.atZone(ZoneId.systemDefault()).toInstant().getEpochSecond();
}


public static LocalDateTime getLocalDateTimeOfMillisecond(long timestamp) {
    Instant instant = Instant.ofEpochMilli(timestamp);
    ZoneId zone = ZoneId.systemDefault();
    return LocalDateTime.ofInstant(instant, zone);
}

public static LocalDateTime getLocalDateTimeOfSecond(long timestamp) {
    Instant instant = Instant.ofEpochSecond(timestamp);
    ZoneId zone = ZoneId.systemDefault();
    return LocalDateTime.ofInstant(instant, zone);
}


/**
 * 获取指定时间的指定格式
 *
 * @param time
 * @param pattern
 * @return
 */
public static String formatTime(LocalDateTime time, String pattern) {
    return time.format(DateTimeFormatter.ofPattern(pattern));
}

/**
 * 获取当前时间的指定格式
 *
 * @param pattern
 * @return
 */
public static String formatNow(String pattern) {
    return formatTime(LocalDateTime.now(), pattern);
}

/**
 * 将字符串按照指定格式转换为时间
 *
 * @param time    要转换的时间字符串
 * @param pattern 格式
 * @return
 */
public static LocalDateTime strToTime(String time, String pattern) {
    return LocalDateTime.parse(time, DateTimeFormatter.ofPattern(pattern));
}

/**
 * 时间加上一个数,根据field不同加不同值,field为ChronoUnit.*
 *
 * @param time
 * @param number
 * @param field
 * @return
 */
public static LocalDateTime plus(LocalDateTime time, long number, TemporalUnit field) {
    return time.plus(number, field);
}


/**
 * 时间减去一个数,根据field不同减不同值,field参数为ChronoUnit.*
 *
 * @param time
 * @param number
 * @param field
 * @return
 */
public static LocalDateTime minu(LocalDateTime time, long number, TemporalUnit field) {
    return time.minus(number, field);
}

/**
 * 获取两个日期的差  field参数为ChronoUnit.*
 *
 * @param startTime
 * @param endTime
 * @param field     单位(年月日时分秒)
 * @return
 */
public static long betweenTwoTime(LocalDateTime startTime, LocalDateTime endTime, ChronoUnit field) {
    Period period = Period.between(LocalDate.from(startTime), LocalDate.from(endTime));
    if (field == ChronoUnit.YEARS) return period.getYears();
    if (field == ChronoUnit.MONTHS) return period.getYears() * 12 + period.getMonths();
    return field.between(startTime, endTime);
}

/**
 * 获取一天的开始时间
 *
 * @param time
 * @return
 */
public static LocalDateTime getDayStart(LocalDateTime time) {
    return LocalDateTime.of(time.toLocalDate(), LocalTime.MIN);
}

/**
 * 获取一天的结束时间
 *
 * @param time
 * @return
 */
public static LocalDateTime getDayEnd(LocalDateTime time) {
    return LocalDateTime.of(time.toLocalDate(), LocalTime.MAX);
}

/**
 * 获取所在周的开始时间，周一的：00:00:00
 *
 * @param time
 * @return
 */
public static LocalDateTime getWeekStart(LocalDateTime time) {
    LocalDateTime monday = time.with(DayOfWeek.MONDAY);
    return getDayStart(monday);
}

/**
 * 获取所在周的结束时间 周日的23:59:59
 *
 * @param time
 * @return
 */
public static LocalDateTime getWeekEnd(LocalDateTime time) {
    LocalDateTime monday = time.with(DayOfWeek.SUNDAY);
    return getDayEnd(monday);
}

/**
 * 获取时间所在月的开始时间
 *
 * @param time
 * @return
 */
public static LocalDateTime getMonthStart(LocalDateTime time) {
    LocalDateTime firstDay = time.with(TemporalAdjusters.firstDayOfMonth());
    return getDayStart(firstDay);
}

/**
 * 获取时间所在月的结束时间
 *
 * @param time
 * @return
 */
public static LocalDateTime getMonthEnd(LocalDateTime time) {
    LocalDateTime lastDay = time.with(TemporalAdjusters.lastDayOfMonth());
    return getDayEnd(lastDay);
}

/**
 * 获取某月的开始时间
 *
 * @param offset 0本月，1下个月，-1上个月，依次类推
 * @return
 */
public static LocalDateTime getMonthStartByOffset(int offset) {
    LocalDateTime lastDay = LocalDateTime.now().plusMonths(offset).with(TemporalAdjusters.firstDayOfMonth());
    return getDayStart(lastDay);
}

/**
 * 获取某月的结束时间
 *
 * @param offset 0本月，1下个月，-1上个月，依次类推
 * @return
 */
public static LocalDateTime getMonthEndByOffset(int offset) {
    LocalDateTime lastDay = LocalDateTime.now().plusMonths(offset).with(TemporalAdjusters.lastDayOfMonth());
    return getDayEnd(lastDay);
}

/**
 * 获取某年的开始时间
 *
 * @param offset offset 0今年，1明年，-1去年，依次类推
 * @return
 */
public static LocalDateTime yearStartByOffset(int offset) {
    LocalDateTime firstDay = LocalDateTime.now().plusYears(offset).with(TemporalAdjusters.firstDayOfYear());
    return getDayStart(firstDay);
}


/**
 * 获取某年的结束时间
 *
 * @param offset offset 0今年，1明年，-1去年，依次类推
 * @return
 */
public static LocalDateTime yearEndByOffset(int offset) {
    LocalDateTime end = LocalDateTime.now().plusYears(offset).with(TemporalAdjusters.lastDayOfYear());
    return getDayEnd(end);
}


/**
 * 获取某周的开始日期时间
 *
 * @param offset 0本周，1下周，-1上周，依次类推
 * @return
 */
public static LocalDateTime weekStartByOffset(int offset) {
    LocalDateTime localDate = LocalDateTime.now().plusWeeks(offset);
    LocalDateTime start = localDate.with(DayOfWeek.MONDAY);
    return getDayStart(start);
}

/**
 * 获取某周的结束日期时间
 *
 * @param offset 0本周，1下周，-1上周，依次类推
 * @return
 */
public static LocalDateTime weekEndByOffset(int offset) {
    LocalDateTime localDate = LocalDateTime.now().plusWeeks(offset);
    LocalDateTime end = localDate.with(DayOfWeek.SUNDAY);
    return getDayEnd(end);
}

/**
 * 比较两个日期相差天数
 *
 * @return
 */
public static int DateDiffer(LocalDate startDate, LocalDate endDate) {
    return Period.between(startDate, endDate).getDays();
}