Java Day Between getDifferenceInDays(final Date startDate, final Date endDate)

Description

Determines the difference in days of two dates

License

Open Source License

Parameter

Parameter	Description
startDate	start date
endDate	end date

Return

number of days

Declaration

public static int getDifferenceInDays(final Date startDate, final Date endDate) 

Method Source Code

//package com.java2s;
/*//from w  ww  .  j av  a  2 s. co  m
 * jGnash, a personal finance application
 * Copyright (C) 2001-2015 Craig Cavanaugh
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

public class Main {
    private static final long MILLISECONDS_PER_DAY = 24 * 60 * 60 * 1000;
    /**
     * ThreadLocal for a {@code GregorianCalendar}
     */
    private static final ThreadLocal<GregorianCalendar> gregorianCalendarThreadLocal = new ThreadLocal<GregorianCalendar>() {
        @Override
        protected GregorianCalendar initialValue() {
            return new GregorianCalendar();
        }
    };

    /**
     * Determines the difference in days of two dates
     *
     * @param startDate start date
     * @param endDate   end date
     * @return number of days
     */
    public static int getDifferenceInDays(final Date startDate, final Date endDate) {
        final GregorianCalendar c = gregorianCalendarThreadLocal.get();

        c.setTime(trimDate(startDate));
        final long startMilli = c.getTimeInMillis() + c.getTimeZone().getOffset(c.getTimeInMillis());

        c.setTime(trimDate(endDate));
        final long endMilli = c.getTimeInMillis() + c.getTimeZone().getOffset(c.getTimeInMillis());

        return (int) ((endMilli - startMilli) / MILLISECONDS_PER_DAY);
    }

    /**
     * Trims the date so that only the day, month, and year are significant.
     *
     * @param date date to trim
     * @return leveled date
     */
    public static Date trimDate(final Date date) {
        final GregorianCalendar c = gregorianCalendarThreadLocal.get();

        c.setTime(date);

        c.set(Calendar.MILLISECOND, 0);
        c.set(Calendar.SECOND, 0);
        c.set(Calendar.MINUTE, 0);
        c.set(Calendar.HOUR_OF_DAY, 0);

        return c.getTime();
    }
}

Related

1. getDiffDays(Date date1, Date date2)
2. getDiffDays(String startDate, String endDate)
3. getDifferDays(Date d1, Date d2)
4. getDifferDays(String date1, String date2)
5. getDifference(Date d1, Date d2)
6. getDifferenceOfDays(String dateFromStr, String dateToStr, String dateFormat)
7. getDifferencesBetweenIndicateDays( final Date minorDate, final Date majorDate)
8. getDiffMilliSeconds(Date form, Date to)
9. getManyWeeksDifference(Date a, Date b)