如何確定特定時間的周五和周日之間的日期

Question

我正在嘗試檢查Java的當前日期和時間是在一周的星期五17:42和星期日17:42之間。

目前，我正在使用非常糟糕的代碼塊進行此操作。 這是一個匆忙的解決方案。 現在我正在重構，但是在joda等中找不到任何方法。

有任何想法嗎？ 謝謝

private final Calendar currentDate = Calendar.getInstance();
private final int day = currentDate.get(Calendar.DAY_OF_WEEK);
private final int hour = currentDate.get(Calendar.HOUR_OF_DAY);
private final int minute = currentDate.get(Calendar.MINUTE);

if (day != 1 && day != 6 && day != 7) {
    if (combined != 0) {
        return badge == 1;
    } else {
        return badge == product;
    }
} else {
    if (day == 6 && hour > 16) {
        if (hour == 17 && minute < 43) {
            if (combined != 0) {
                return badge == 1;
            } else {
                return badge == product;
            }
        } else {
            return badge == 0;
        }
    } else if (day == 6 && hour < 17) {
        if (combined != 0) {
            return badge == 1;
        } else {
            return badge == product;
        }
    } else if (day == 1 && hour > 16) {
        if (hour == 17 && minute < 43) {
            return badge == 0;
        } else {
            if (combined != 0) {
                return badge == 1;
            } else {
                return badge == product;
            }
        }
    } else {
        return badge == 0;
    }
}

我在@MadProgrammer和@Meno Hochschild的幫助下使用了這樣的解決方案

方法：

public static boolean isBetween(LocalDateTime check, LocalDateTime startTime, LocalDateTime endTime) {
 return ((check.equals(startTime) || check.isAfter(startTime)) && (check.equals(endTime) || check.isBefore(endTime))); }

用法：

static LocalDateTime now = LocalDateTime.now();
static LocalDateTime friday = now.with(DayOfWeek.FRIDAY).toLocalDate().atTime(17, 41);
static LocalDateTime sunday = friday.plusDays(2).plusMinutes(1);

if (!isBetween(now, friday, sunday)) { ... }

再次感謝您的努力。

Answer 1

Date和Calendar具有可以對Date / Calendar其他實例進行比較的方法， equals ， before和after

但是，我鼓勵使用Java 8的新Time API

public static boolean isBetween(LocalDateTime check, LocalDateTime startTime, LocalDateTime endTime) {
    return ((check.equals(startTime) || check.isAfter(startTime)) && 
                    (check.equals(endTime) || check.isBefore(endTime)));
}

如果提供的LocalDateTime在指定范圍內（包括LocalDateTime ），它將返回true 。

就像是...

LocalDateTime start = LocalDateTime.now();
start = start.withDayOfMonth(26).withHour(17).withMinute(42).withSecond(0).withNano(0);
LocalDateTime end = start.plusDays(2);

LocalDateTime check = LocalDateTime.now();

System.out.println(check + " is within range = " + isBetween(check, start, end));
check = start;
System.out.println(check + " is within range = " + isBetween(check, start, end));
check = end;
System.out.println(check + " is within range = " + isBetween(check, start, end));
check = start.plusDays(1);
System.out.println(check + " is within range = " + isBetween(check, start, end));
check = end.plusMinutes(1);
System.out.println(check + " is within range = " + isBetween(check, start, end));

哪個輸出

2015-06-25T18:31:32.969 is within range = false
2015-06-26T17:42 is within range = true
2015-06-28T17:42 is within range = true
2015-06-27T17:42 is within range = true
2015-06-28T17:43 is within range = false

Joda-Time的Interval類使它變得更加輕松

Interval targetInterval = new Interval(targetStart, targetEnd);
System.out.println("Contains interval = " + interval.contains(targetInterval)

在這里演示

另一種方法

所以我在考慮回家的路上，假設您擁有的只是要檢查的日期/時間，如何確定一天是否在您的范圍內

LocalDateTime now = LocalDateTime.now();
boolean isBetween = false;
switch (now.getDayOfWeek()) {
    case FRIDAY:
    case SATURDAY:
    case SUNDAY:
        LocalDateTime lastFriday = getLastFriday(now);
        LocalDateTime nextSunday = getNextSunday(now);
        isBetween = isBetween(now, lastFriday, nextSunday);
        System.out.println(lastFriday + " - " + nextSunday + ": " + end);
        break;
}

這樣做是檢查dayOfWeek以查看其是否在所需范圍內，如果是，它將查找指定日期的上一個Friday和下一個Sunday ，並檢查它是否介於兩者之間（請參閱前面的示例）

lastFriday和nextSunday只需從指定的日期/時間開始增加/減去day ，直到達到所需的dayOfWeek ，然后播種所需的時間約束

public static LocalDateTime getLastFriday(LocalDateTime anchor) {
    LocalDateTime ldt = LocalDateTime.from(anchor);
    return ldt.with(DayOfWeek.FRIDAY).withHour(17).withMinute(42).withSecond(0).withNano(0);
}

public static LocalDateTime getNextSunday(LocalDateTime anchor) {
    LocalDateTime ldt = LocalDateTime.from(anchor);
    return ldt.with(DayOfWeek.SUNDAY).withHour(17).withMinute(42).withSecond(0).withNano(0);
}

Answer 2

使用Calendar您可以知道給定的日期是DAY_OF_WEEK ，然后只需檢查小時數即可：

Calendar c = Calendar.getInstance();
int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);
int hour = c.get(Calendar.HOUR_OF_DAY);
int minute = c.get(Calendar.MINUTE);

// in friday the hour must be greater than 17:42
if (dayOfWeek == 5 && ((hour > 17) || (hour == 17 && minute >= 42)) {
    // successss!!
}
// days from 1 to 7... saturday(6) all day
if (dayOfWeek == 6) {
    // successss!!
}
// sunday hour must be lower than 17:42
if (dayOfWeek == 7 && ((hour < 17) || (hour == 17 && minute <= 42)) {
    // successss!!
}

Answer 3

使用舊的Java的更好的解決方案如下所示：

// current timestamp
GregorianCalendar gcal = new GregorianCalendar();

// specify ISO-week (you are searching for friday until sunday in this order)
gcal.setMinimalDaysInFirstWeek(4);
gcal.setFirstDayOfWeek(Calendar.MONDAY);

// sunday at 17:43
GregorianCalendar sunday = (GregorianCalendar) gcal.clone();
sunday.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
sunday.set(Calendar.HOUR_OF_DAY, 17);
sunday.set(Calendar.MINUTE, 43);
sunday.set(Calendar.SECOND, 0);
sunday.set(Calendar.MILLISECOND, 0);

// friday at 17:42
GregorianCalendar friday = (GregorianCalendar) sunday.clone();
friday.add(Calendar.DATE, -2);
friday.add(Calendar.MINUTE, -1);

// logging for test purposes
SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
System.out.println(f.format(friday.getTime()));
System.out.println(f.format(gcal.getTime()));
System.out.println(f.format(sunday.getTime()));

// result (assumption: half-open-interval)
boolean withinTimeWindow = !gcal.before(friday) && gcal.before(sunday);

Java-8提供了一種較短的方法（假設使用ISO-weekmodel）：

LocalDateTime now = LocalDateTime.now();
LocalDateTime friday = now.with(DayOfWeek.FRIDAY).toLocalDate().atTime(17, 42);
LocalDateTime sunday = friday.plusDays(2).plusMinutes(1);
boolean withinTimeWindow = !now.isBefore(friday) && now.isBefore(sunday);

最后，您的等效評估結果可能如下所示：

  if (!withinTimeWindow) {
        if (combined != 0) {
            return badge == 1;
        } else {
            return badge == product;
        }
  } else {
        return badge == 0;
  }