Mega Code Archive
Checks if two calendars represent the same day ignoring time
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import java.util.Calendar;
import java.util.Date;
public class DateUtils {
/**
* <p>Checks if two dates are on the same day ignoring time.</p>
* @param date1 the first date, not altered, not null
* @param date2 the second date, not altered, not null
* @return true if they represent the same day
* @throws IllegalArgumentException if either date is <code>null</code>
*/
public static boolean isSameDay(Date date1, Date date2) {
if (date1 == null || date2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
Calendar cal1 = Calendar.getInstance();
cal1.setTime(date1);
Calendar cal2 = Calendar.getInstance();
cal2.setTime(date2);
return isSameDay(cal1, cal2);
}
/**
* <p>Checks if two calendars represent the same day ignoring time.</p>
* @param cal1 the first calendar, not altered, not null
* @param cal2 the second calendar, not altered, not null
* @return true if they represent the same day
* @throws IllegalArgumentException if either calendar is <code>null</code>
*/
public static boolean isSameDay(Calendar cal1, Calendar cal2) {
if (cal1 == null || cal2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
return (cal1.get(Calendar.ERA) == cal2.get(Calendar.ERA) &&
cal1.get(Calendar.YEAR) == cal2.get(Calendar.YEAR) &&
cal1.get(Calendar.DAY_OF_YEAR) == cal2.get(Calendar.DAY_OF_YEAR));
}
/**
* <p>Checks if a date is today.</p>
* @param date the date, not altered, not null.
* @return true if the date is today.
* @throws IllegalArgumentException if the date is <code>null</code>
*/
public static boolean isToday(Date date) {
return isSameDay(date, Calendar.getInstance().getTime());
}
/**
* <p>Checks if a calendar date is today.</p>
* @param cal the calendar, not altered, not null
* @return true if cal date is today
* @throws IllegalArgumentException if the calendar is <code>null</code>
*/
public static boolean isToday(Calendar cal) {
return isSameDay(cal, Calendar.getInstance());
}
/**
* <p>Checks if the first date is before the second date ignoring time.</p>
* @param date1 the first date, not altered, not null
* @param date2 the second date, not altered, not null
* @return true if the first date day is before the second date day.
* @throws IllegalArgumentException if the date is <code>null</code>
*/
public static boolean isBeforeDay(Date date1, Date date2) {
if (date1 == null || date2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
Calendar cal1 = Calendar.getInstance();
cal1.setTime(date1);
Calendar cal2 = Calendar.getInstance();
cal2.setTime(date2);
return isBeforeDay(cal1, cal2);
}
/**
* <p>Checks if the first calendar date is before the second calendar date ignoring time.</p>
* @param cal1 the first calendar, not altered, not null.
* @param cal2 the second calendar, not altered, not null.
* @return true if cal1 date is before cal2 date ignoring time.
* @throws IllegalArgumentException if either of the calendars are <code>null</code>
*/
public static boolean isBeforeDay(Calendar cal1, Calendar cal2) {
if (cal1 == null || cal2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
if (cal1.get(Calendar.ERA) < cal2.get(Calendar.ERA)) return true;
if (cal1.get(Calendar.ERA) > cal2.get(Calendar.ERA)) return false;
if (cal1.get(Calendar.YEAR) < cal2.get(Calendar.YEAR)) return true;
if (cal1.get(Calendar.YEAR) > cal2.get(Calendar.YEAR)) return false;
return cal1.get(Calendar.DAY_OF_YEAR) < cal2.get(Calendar.DAY_OF_YEAR);
}
/**
* <p>Checks if the first date is after the second date ignoring time.</p>
* @param date1 the first date, not altered, not null
* @param date2 the second date, not altered, not null
* @return true if the first date day is after the second date day.
* @throws IllegalArgumentException if the date is <code>null</code>
*/
public static boolean isAfterDay(Date date1, Date date2) {
if (date1 == null || date2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
Calendar cal1 = Calendar.getInstance();
cal1.setTime(date1);
Calendar cal2 = Calendar.getInstance();
cal2.setTime(date2);
return isAfterDay(cal1, cal2);
}
/**
* <p>Checks if the first calendar date is after the second calendar date ignoring time.</p>
* @param cal1 the first calendar, not altered, not null.
* @param cal2 the second calendar, not altered, not null.
* @return true if cal1 date is after cal2 date ignoring time.
* @throws IllegalArgumentException if either of the calendars are <code>null</code>
*/
public static boolean isAfterDay(Calendar cal1, Calendar cal2) {
if (cal1 == null || cal2 == null) {
throw new IllegalArgumentException("The dates must not be null");
}
if (cal1.get(Calendar.ERA) < cal2.get(Calendar.ERA)) return false;
if (cal1.get(Calendar.ERA) > cal2.get(Calendar.ERA)) return true;
if (cal1.get(Calendar.YEAR) < cal2.get(Calendar.YEAR)) return false;
if (cal1.get(Calendar.YEAR) > cal2.get(Calendar.YEAR)) return true;
return cal1.get(Calendar.DAY_OF_YEAR) > cal2.get(Calendar.DAY_OF_YEAR);
}
/**
* <p>Checks if a date is after today and within a number of days in the future.</p>
* @param date the date to check, not altered, not null.
* @param days the number of days.
* @return true if the date day is after today and within days in the future .
* @throws IllegalArgumentException if the date is <code>null</code>
*/
public static boolean isWithinDaysFuture(Date date, int days) {
if (date == null) {
throw new IllegalArgumentException("The date must not be null");
}
Calendar cal = Calendar.getInstance();
cal.setTime(date);
return isWithinDaysFuture(cal, days);
}
/**
* <p>Checks if a calendar date is after today and within a number of days in the future.</p>
* @param cal the calendar, not altered, not null
* @param days the number of days.
* @return true if the calendar date day is after today and within days in the future .
* @throws IllegalArgumentException if the calendar is <code>null</code>
*/
public static boolean isWithinDaysFuture(Calendar cal, int days) {
if (cal == null) {
throw new IllegalArgumentException("The date must not be null");
}
Calendar today = Calendar.getInstance();
Calendar future = Calendar.getInstance();
future.add(Calendar.DAY_OF_YEAR, days);
return (isAfterDay(cal, today) && ! isAfterDay(cal, future));
}
/** Returns the given date with the time set to the start of the day. */
public static Date getStart(Date date) {
return clearTime(date);
}
/** Returns the given date with the time values cleared. */
public static Date clearTime(Date date) {
if (date == null) {
return null;
}
Calendar c = Calendar.getInstance();
c.setTime(date);
c.set(Calendar.HOUR_OF_DAY, 0);
c.set(Calendar.MINUTE, 0);
c.set(Calendar.SECOND, 0);
c.set(Calendar.MILLISECOND, 0);
return c.getTime();
}
/** Determines whether or not a date has any time values (hour, minute,
* seconds or millisecondsReturns the given date with the time values cleared. */
/**
* Determines whether or not a date has any time values.
* @param date The date.
* @return true iff the date is not null and any of the date's hour, minute,
* seconds or millisecond values are greater than zero.
*/
public static boolean hasTime(Date date) {
if (date == null) {
return false;
}
Calendar c = Calendar.getInstance();
c.setTime(date);
if (c.get(Calendar.HOUR_OF_DAY) > 0) {
return true;
}
if (c.get(Calendar.MINUTE) > 0) {
return true;
}
if (c.get(Calendar.SECOND) > 0) {
return true;
}
if (c.get(Calendar.MILLISECOND) > 0) {
return true;
}
return false;
}
/** Returns the given date with time set to the end of the day */
public static Date getEnd(Date date) {
if (date == null) {
return null;
}
Calendar c = Calendar.getInstance();
c.setTime(date);
c.set(Calendar.HOUR_OF_DAY, 23);
c.set(Calendar.MINUTE, 59);
c.set(Calendar.SECOND, 59);
c.set(Calendar.MILLISECOND, 999);
return c.getTime();
}
/**
* Returns the maximum of two dates. A null date is treated as being less
* than any non-null date.
*/
public static Date max(Date d1, Date d2) {
if (d1 == null && d2 == null) return null;
if (d1 == null) return d2;
if (d2 == null) return d1;
return (d1.after(d2)) ? d1 : d2;
}
/**
* Returns the minimum of two dates. A null date is treated as being greater
* than any non-null date.
*/
public static Date min(Date d1, Date d2) {
if (d1 == null && d2 == null) return null;
if (d1 == null) return d2;
if (d2 == null) return d1;
return (d1.before(d2)) ? d1 : d2;
}
/** The maximum date possible. */
public static Date MAX_DATE = new Date(Long.MAX_VALUE);
}
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