/*
* $Id$
*
* Copyright 2007 Sun Microsystems, Inc., 4150 Network Circle,
* Santa Clara, California 95054, U.S.A. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.jdesktop.swingx.calendar;
import java.util.Calendar;
import java.util.Date;
/**
* Calendar manipulation.
*
* PENDING: replace by something tested - as is c&p'ed dateUtils
* to work on a calendar instead of using long
*
* @author Jeanette Winzenburg
*/
public class CalendarUtils {
// Constants used internally; unit is milliseconds
@SuppressWarnings("unused")
public static final int ONE_MINUTE = 60*1000;
@SuppressWarnings("unused")
public static final int ONE_HOUR = 60*ONE_MINUTE;
@SuppressWarnings("unused")
public static final int THREE_HOURS = 3 * ONE_HOUR;
@SuppressWarnings("unused")
public static final int ONE_DAY = 24*ONE_HOUR;
public static final int DECADE = 5467;
public static final int YEAR_IN_DECADE = DECADE + 1;
/**
* Increments the calendar field of the given calendar by amount.
*
* @param calendar
* @param field the field to increment, allowed are all fields known to
* Calendar plus DECADE.
* @param amount
*
* @throws IllegalArgumentException
*/
public static void add(Calendar calendar, int field, int amount) {
if (isNativeField(field)) {
calendar.add(field, amount);
} else {
switch (field) {
case DECADE:
calendar.add(Calendar.YEAR, amount * 10);
break;
default:
throw new IllegalArgumentException("unsupported field: " + field);
}
}
}
/**
* Gets the calendar field of the given calendar by amount.
*
* @param calendar
* @param field the field to get, allowed are all fields known to
* Calendar plus DECADE.
*
* @throws IllegalArgumentException
*/
public static int get(Calendar calendar, int field) {
if (isNativeField(field)) {
return calendar.get(field);
}
switch (field) {
case DECADE:
return decade(calendar.get(Calendar.YEAR));
case YEAR_IN_DECADE:
return calendar.get(Calendar.YEAR) % 10;
default:
throw new IllegalArgumentException("unsupported field: " + field);
}
}
/**
* Sets the calendar field of the given calendar by amount. <p>
*
* NOTE: the custom field implementations are very naive (JSR-310 will do better)
* - for decade: value must be positive, value must be a multiple of 10 and is interpreted as the
* first-year-of-the-decade
* - for year-in-decade: value is added/substracted to/from the start-of-decade of the
* date of the given calendar
*
* @param calendar
* @param field the field to increment, allowed are all fields known to
* Calendar plus DECADE.
* @param value the decade to set, must be a
*
* @throws IllegalArgumentException if the field is unsupported or the value is
* not dividable by 10 or negative.
*/
public static void set(Calendar calendar, int field, int value) {
if (isNativeField(field)) {
calendar.set(field, value);
} else {
switch (field) {
case DECADE:
if(value <= 0 ) {
throw new IllegalArgumentException("value must be a positive but was: " + value);
}
if (value % 10 != 0) {
throw new IllegalArgumentException("value must be a multiple of 10 but was: " + value);
}
int yearInDecade = get(calendar, YEAR_IN_DECADE);
calendar.set(Calendar.YEAR, value + yearInDecade);
break;
case YEAR_IN_DECADE:
int decade = get(calendar, DECADE);
calendar.set(Calendar.YEAR, value + decade);
break;
default:
throw new IllegalArgumentException("unsupported field: " + field);
}
}
}
/**
* @param calendarField
* @return
*/
private static boolean isNativeField(int calendarField) {
return calendarField < DECADE;
}
/**
* Adjusts the Calendar to the end of the day of the last day in DST in the
* current year or unchanged if not using DST. Returns the calendar's date or null, if not
* using DST.<p>
*
*
* @param calendar the calendar to adjust
* @return the end of day of the last day in DST, or null if not using DST.
*/
public static Date getEndOfDST(Calendar calendar) {
if (!calendar.getTimeZone().useDaylightTime()) return null;
long old = calendar.getTimeInMillis();
calendar.set(Calendar.MONTH, Calendar.DECEMBER);
endOfMonth(calendar);
startOfDay(calendar);
for (int i = 0; i < 366; i++) {
calendar.add(Calendar.DATE, -1);
if (calendar.getTimeZone().inDaylightTime(calendar.getTime())) {
endOfDay(calendar);
return calendar.getTime();
}
}
calendar.setTimeInMillis(old);
return null;
}
/**
* Adjusts the Calendar to the end of the day of the first day in DST in the
* current year or unchanged if not using DST. Returns the calendar's date or null, if not
* using DST.<p>
*
* Note: the start of the day of the first day in DST is ill-defined!
*
* @param calendar the calendar to adjust
* @return the start of day of the first day in DST, or null if not using DST.
*/
public static Date getStartOfDST(Calendar calendar) {
if (!calendar.getTimeZone().useDaylightTime()) return null;
long old = calendar.getTimeInMillis();
calendar.set(Calendar.MONTH, Calendar.JANUARY);
startOfMonth(calendar);
endOfDay(calendar);
for (int i = 0; i < 366; i++) {
calendar.add(Calendar.DATE, 1);
if (calendar.getTimeZone().inDaylightTime(calendar.getTime())) {
endOfDay(calendar);
return calendar.getTime();
}
}
calendar.setTimeInMillis(old);
return null;
}
/**
* Returns a boolean indicating if the given calendar represents the
* start of a day (in the calendar's time zone). The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the start of the day,
* false otherwise.
*/
public static boolean isStartOfDay(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, -1);
return temp.get(Calendar.DATE) != calendar.get(Calendar.DATE);
}
/**
* Returns a boolean indicating if the given calendar represents the
* end of a day (in the calendar's time zone). The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the end of the day,
* false otherwise.
*/
public static boolean isEndOfDay(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, 1);
return temp.get(Calendar.DATE) != calendar.get(Calendar.DATE);
}
/**
* Returns a boolean indicating if the given calendar represents the
* start of a month (in the calendar's time zone). Returns true, if the time is
* the start of the first day of the month, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the start of the first day of the month,
* false otherwise.
*/
public static boolean isStartOfMonth(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, -1);
return temp.get(Calendar.MONTH) != calendar.get(Calendar.MONTH);
}
/**
* Returns a boolean indicating if the given calendar represents the
* end of a month (in the calendar's time zone). Returns true, if the time is
* the end of the last day of the month, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the end of the last day of the month,
* false otherwise.
*/
public static boolean isEndOfMonth(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, 1);
return temp.get(Calendar.MONTH) != calendar.get(Calendar.MONTH);
}
/**
* Returns a boolean indicating if the given calendar represents the
* start of a month (in the calendar's time zone). Returns true, if the time is
* the start of the first day of the month, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the start of the first day of the month,
* false otherwise.
*/
public static boolean isStartOfWeek(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, -1);
return temp.get(Calendar.WEEK_OF_YEAR) != calendar.get(Calendar.WEEK_OF_YEAR);
}
/**
* Returns a boolean indicating if the given calendar represents the
* end of a week (in the calendar's time zone). Returns true, if the time is
* the end of the last day of the week, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the end of the last day of the week,
* false otherwise.
*/
public static boolean isEndOfWeek(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, 1);
return temp.get(Calendar.WEEK_OF_YEAR) != calendar.get(Calendar.WEEK_OF_YEAR);
}
/**
* Adjusts the calendar to the start of the current week.
* That is, first day of the week with all time fields cleared.
* @param calendar the calendar to adjust.
* @return the Date the calendar is set to
*/
public static void startOfWeek(Calendar calendar) {
calendar.set(Calendar.DAY_OF_WEEK, calendar.getFirstDayOfWeek());
startOfDay(calendar);
}
/**
* Adjusts the calendar to the end of the current week.
* That is, last day of the week with all time fields at max.
* @param calendar the calendar to adjust.
*/
public static void endOfWeek(Calendar calendar) {
startOfWeek(calendar);
calendar.add(Calendar.DATE, 7);
calendar.add(Calendar.MILLISECOND, -1);
}
/**
* Adjusts the calendar to the end of the current week.
* That is, last day of the week with all time fields at max.
* The Date of the adjusted Calendar is
* returned.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the end of the week of the given date
*/
public static Date endOfWeek(Calendar calendar, Date date) {
calendar.setTime(date);
endOfWeek(calendar);
return calendar.getTime();
}
/**
* Adjusts the calendar to the start of the current week.
* That is, last day of the week with all time fields at max.
* The Date of the adjusted Calendar is
* returned.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the start of the week of the given date
*/
public static Date startOfWeek(Calendar calendar, Date date) {
calendar.setTime(date);
startOfWeek(calendar);
return calendar.getTime();
}
/**
* Adjusts the given Calendar to the start of the decade.
*
* @param calendar the calendar to adjust.
*/
public static void startOfDecade(Calendar calendar) {
calendar.set(Calendar.YEAR, decade(calendar.get(Calendar.YEAR)) );
startOfYear(calendar);
}
/**
* @param year
* @return
*/
private static int decade(int year) {
return (year / 10) * 10;
}
/**
* Adjusts the given Calendar to the start of the decade as defined by
* the given date. Returns the calendar's Date.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the start of the decade of the given date
*/
public static Date startOfDecade(Calendar calendar, Date date) {
calendar.setTime(date);
startOfDecade(calendar);
return calendar.getTime();
}
/**
* Returns a boolean indicating if the given calendar represents the
* start of a decade (in the calendar's time zone). Returns true, if the time is
* the start of the first day of the decade, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the start of the first day of the month,
* false otherwise.
*/
public static boolean isStartOfDecade(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, -1);
return decade(temp.get(Calendar.YEAR)) != decade(calendar.get(Calendar.YEAR));
}
/**
* Adjusts the given Calendar to the start of the year.
*
* @param calendar the calendar to adjust.
*/
public static void startOfYear(Calendar calendar) {
calendar.set(Calendar.MONTH, Calendar.JANUARY);
startOfMonth(calendar);
}
/**
* Adjusts the given Calendar to the start of the year as defined by
* the given date. Returns the calendar's Date.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the start of the year of the given date
*/
public static Date startOfYear(Calendar calendar, Date date) {
calendar.setTime(date);
startOfYear(calendar);
return calendar.getTime();
}
/**
* Returns a boolean indicating if the given calendar represents the
* start of a year (in the calendar's time zone). Returns true, if the time is
* the start of the first day of the year, false otherwise. The calendar is unchanged.
*
* @param calendar the calendar to check.
*
* @return true if the calendar's time is the start of the first day of the month,
* false otherwise.
*/
public static boolean isStartOfYear(Calendar calendar) {
Calendar temp = (Calendar) calendar.clone();
temp.add(Calendar.MILLISECOND, -1);
return temp.get(Calendar.YEAR) != calendar.get(Calendar.YEAR);
}
/**
* Adjusts the calendar to the start of the current month.
* That is, first day of the month with all time fields cleared.
*
* @param calendar calendar to adjust.
*/
public static void startOfMonth(Calendar calendar) {
calendar.set(Calendar.DAY_OF_MONTH, 1);
startOfDay(calendar);
}
/**
* Adjusts the calendar to the end of the current month.
* That is the last day of the month with all time-fields
* at max.
*
* @param calendar calendar to adjust.
*/
public static void endOfMonth(Calendar calendar) {
// start of next month
calendar.add(Calendar.MONTH, 1);
startOfMonth(calendar);
// one millisecond back
calendar.add(Calendar.MILLISECOND, -1);
}
/**
* Adjust the given calendar to the first millisecond of the given date.
* that is all time fields cleared. The Date of the adjusted Calendar is
* returned.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the start of the day of the given date
*/
public static Date startOfDay(Calendar calendar, Date date) {
calendar.setTime(date);
startOfDay(calendar);
return calendar.getTime();
}
/**
* Adjust the given calendar to the last millisecond of the given date.
* that is all time fields cleared. The Date of the adjusted Calendar is
* returned.
*
* @param calendar calendar to adjust.
* @param date the Date to use.
* @return the end of the day of the given date
*/
public static Date endOfDay(Calendar calendar, Date date) {
calendar.setTime(date);
endOfDay(calendar);
return calendar.getTime();
}
/**
* Adjust the given calendar to the first millisecond of the current day.
* that is all time fields cleared.
*
* @param calendar calendar to adjust.
*/
public static void startOfDay(Calendar calendar) {
calendar.set(Calendar.HOUR_OF_DAY, 0);
calendar.set(Calendar.MILLISECOND, 0);
calendar.set(Calendar.SECOND, 0);
calendar.set(Calendar.MINUTE, 0);
calendar.getTimeInMillis();
}
/**
* Adjust the given calendar to the last millisecond of the specified date.
*
* @param calendar calendar to adjust.
*/
public static void endOfDay(Calendar calendar) {
calendar.add(Calendar.DATE, 1);
startOfDay(calendar);
calendar.add(Calendar.MILLISECOND, -1);
}
/**
* Adjusts the given calendar to the start of the period as indicated by the
* given field. This delegates to startOfDay, -Week, -Month, -Year as appropriate.
*
* @param calendar
* @param field the period to adjust, allowed are Calendar.DAY_OF_MONTH, -.MONTH,
* -.WEEK and YEAR and CalendarUtils.DECADE.
*/
public static void startOf(Calendar calendar, int field) {
switch (field) {
case Calendar.DAY_OF_MONTH:
startOfDay(calendar);
break;
case Calendar.MONTH:
startOfMonth(calendar);
break;
case Calendar.WEEK_OF_YEAR:
startOfWeek(calendar);
break;
case Calendar.YEAR:
startOfYear(calendar);
break;
case DECADE:
startOfDecade(calendar);
break;
default:
throw new IllegalArgumentException("unsupported field: " + field);
}
}
/**
* Returns a boolean indicating if the calendar is set to the start of a
* period as defined by the
* given field. This delegates to startOfDay, -Week, -Month, -Year as appropriate.
* The calendar is unchanged.
*
* @param calendar
* @param field the period to adjust, allowed are Calendar.DAY_OF_MONTH, -.MONTH,
* -.WEEK and YEAR and CalendarUtils.DECADE.
* @throws IllegalArgumentException if the field is not supported.
*/
public static boolean isStartOf(Calendar calendar, int field) {
switch (field) {
case Calendar.DAY_OF_MONTH:
return isStartOfDay(calendar);
case Calendar.MONTH:
return isStartOfMonth(calendar);
case Calendar.WEEK_OF_YEAR:
return isStartOfWeek(calendar);
case Calendar.YEAR:
return isStartOfYear(calendar);
case DECADE:
return isStartOfDecade(calendar);
default:
throw new IllegalArgumentException("unsupported field: " + field);
}
}
/**
* Checks the given dates for being equal.
*
* @param current one of the dates to compare
* @param date the otherr of the dates to compare
* @return true if the two given dates both are null or both are not null and equal,
* false otherwise.
*/
public static boolean areEqual(Date current, Date date) {
if ((date == null) && (current == null)) {
return true;
}
if (date != null) {
return date.equals(current);
}
return false;
}
/**
* Returns a boolean indicating whether the given Date is the same day as
* the day in the calendar. Calendar and date are unchanged by the check.
*
* @param today the Calendar representing a date, must not be null.
* @param now the date to compare to, must not be null
* @return true if the calendar and date represent the same day in the
* given calendar.
*/
public static boolean isSameDay(Calendar today, Date now) {
Calendar temp = (Calendar) today.clone();
startOfDay(temp);
Date start = temp.getTime();
temp.setTime(now);
startOfDay(temp);
return start.equals(temp.getTime());
}
/**
* Returns a boolean indicating whether the given Date is in the same period as
* the Date in the calendar, as defined by the calendar field.
* Calendar and date are unchanged by the check.
*
* @param today the Calendar representing a date, must not be null.
* @param now the date to compare to, must not be null
* @return true if the calendar and date represent the same day in the
* given calendar.
*/
public static boolean isSame(Calendar today, Date now, int field) {
Calendar temp = (Calendar) today.clone();
startOf(temp, field);
Date start = temp.getTime();
temp.setTime(now);
startOf(temp, field);
return start.equals(temp.getTime());
}
/**
* Returns a boolean to indicate whether the given calendar is flushed. <p>
*
* The only way to guarantee a flushed state is to let client code call
* getTime or getTimeInMillis. See
*
* <a href=http://forums.java.net/jive/thread.jspa?threadID=74472&tstart=0>Despairing
* in Calendar</a>
* <p>
* Note: this if for testing only and not entirely safe!
*
* @param calendar
* @return
*/
public static boolean isFlushed(Calendar calendar) {
return !calendar.toString().contains("time=?");
}
}