/*
* Copyright (c) 2008, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name "TwelveMonkeys" nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.twelvemonkeys.lang;
import java.util.Date;
import java.util.TimeZone;
/**
* A utility class with useful date manipulation methods and constants.
* <p/>
*
* @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>
* @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/lang/DateUtil.java#1 $
*/
public final class DateUtil {
/** One second: 1000 milliseconds. */
public static final long SECOND = 1000l;
/** One minute: 60 seconds (60 000 milliseconds). */
public static final long MINUTE = 60l * SECOND;
/**
* One hour: 60 minutes (3 600 000 milliseconds).
* 60 minutes = 3 600 seconds = 3 600 000 milliseconds
*/
public static final long HOUR = 60l * MINUTE;
/**
* One day: 24 hours (86 400 000 milliseconds).
* 24 hours = 1 440 minutes = 86 400 seconds = 86 400 000 milliseconds.
*/
public static final long DAY = 24l * HOUR;
/**
* One calendar year: 365.2425 days (31556952000 milliseconds).
* 365.2425 days = 8765.82 hours = 525949.2 minutes = 31556952 seconds
* = 31556952000 milliseconds.
*/
public static final long CALENDAR_YEAR = 3652425l * 24l * 60l * 6l;
private DateUtil() {
}
/**
* Returns the time between the given start time and now (as defined by
* {@link System#currentTimeMillis()}).
*
* @param pStart the start time
*
* @return the time between the given start time and now.
*/
public static long delta(long pStart) {
return System.currentTimeMillis() - pStart;
}
/**
* Returns the time between the given start time and now (as defined by
* {@link System#currentTimeMillis()}).
*
* @param pStart the start time
*
* @return the time between the given start time and now.
*/
public static long delta(Date pStart) {
return System.currentTimeMillis() - pStart.getTime();
}
/**
* Gets the current time, rounded down to the closest second.
* Equivalent to invoking
* {@code roundToSecond(System.currentTimeMillis())}.
*
* @return the current time, rounded to the closest second.
*/
public static long currentTimeSecond() {
return roundToSecond(System.currentTimeMillis());
}
/**
* Gets the current time, rounded down to the closest minute.
* Equivalent to invoking
* {@code roundToMinute(System.currentTimeMillis())}.
*
* @return the current time, rounded to the closest minute.
*/
public static long currentTimeMinute() {
return roundToMinute(System.currentTimeMillis());
}
/**
* Gets the current time, rounded down to the closest hour.
* Equivalent to invoking
* {@code roundToHour(System.currentTimeMillis())}.
*
* @return the current time, rounded to the closest hour.
*/
public static long currentTimeHour() {
return roundToHour(System.currentTimeMillis());
}
/**
* Gets the current time, rounded down to the closest day.
* Equivalent to invoking
* {@code roundToDay(System.currentTimeMillis())}.
*
* @return the current time, rounded to the closest day.
*/
public static long currentTimeDay() {
return roundToDay(System.currentTimeMillis());
}
/**
* Rounds the given time down to the closest second.
*
* @param pTime time
* @return the time rounded to the closest second.
*/
public static long roundToSecond(final long pTime) {
return (pTime / SECOND) * SECOND;
}
/**
* Rounds the given time down to the closest minute.
*
* @param pTime time
* @return the time rounded to the closest minute.
*/
public static long roundToMinute(final long pTime) {
return (pTime / MINUTE) * MINUTE;
}
/**
* Rounds the given time down to the closest hour, using the default timezone.
*
* @param pTime time
* @return the time rounded to the closest hour.
*/
public static long roundToHour(final long pTime) {
return roundToHour(pTime, TimeZone.getDefault());
}
/**
* Rounds the given time down to the closest hour, using the given timezone.
*
* @param pTime time
* @param pTimeZone the timezone to use when rounding
* @return the time rounded to the closest hour.
*/
public static long roundToHour(final long pTime, final TimeZone pTimeZone) {
int offset = pTimeZone.getOffset(pTime);
return ((pTime / HOUR) * HOUR) - offset;
}
/**
* Rounds the given time down to the closest day, using the default timezone.
*
* @param pTime time
* @return the time rounded to the closest day.
*/
public static long roundToDay(final long pTime) {
return roundToDay(pTime, TimeZone.getDefault());
}
/**
* Rounds the given time down to the closest day, using the given timezone.
*
* @param pTime time
* @param pTimeZone the timezone to use when rounding
* @return the time rounded to the closest day.
*/
public static long roundToDay(final long pTime, final TimeZone pTimeZone) {
int offset = pTimeZone.getOffset(pTime);
return (((pTime + offset) / DAY) * DAY) - offset;
}
}