Java Week Day getFirstDayOfLastWeek(Date date)

Description

get First Day Of Last Week

License

Apache License

Declaration

public static Date getFirstDayOfLastWeek(Date date) 

Method Source Code

//package com.java2s;
/*/*www. j ava2  s  .  c om*/
 *    Copyright (c) 2015 Power Group.
 *     Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 *
 */

import java.util.*;

public class Main {
    public static final int SECOND = 1;
    public static final int MINUTE = 2;

    public static Date getFirstDayOfLastWeek(Date date) {
        Calendar c = Calendar.getInstance();
        c.setTimeInMillis(date.getTime() - 604800000L);
        c.set(Calendar.HOUR_OF_DAY, 0);
        c.set(Calendar.MINUTE, 0);
        c.set(Calendar.SECOND, 0);
        Date lastWeekDate = c.getTime();

        c = new GregorianCalendar();
        c.setFirstDayOfWeek(Calendar.MONDAY);
        c.setTime(new Date(lastWeekDate.getTime()));
        c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek()); // Monday
        return c.getTime();
    }

    public static Date getFirstDayOfWeek(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        return getADayOfWeek(calendar, Calendar.MONDAY).getTime();
    }

    private static Calendar getADayOfWeek(Calendar day, int dayOfWeek) {
        int week = day.get(Calendar.DAY_OF_WEEK);
        if (week == dayOfWeek) {
            return day;
        }
        int diffDay = dayOfWeek - week;
        if (week == Calendar.SUNDAY) {
            diffDay -= 7;
        } else if (dayOfWeek == Calendar.SUNDAY) {
            diffDay += 7;
        }
        day.add(Calendar.DATE, diffDay);
        return day;
    }
}

Related

1. getDayOfWeekShortString(Date date)
2. getDaysExceptWeekend(String from, String to)
3. getDayWithWeek(Date date)
4. getENWeekDay()
5. getFirstday_Lastday_Week()
6. getFirstDayOfWeek()
7. getFirstDayOfWeek()
8. getFirstDayOfWeek(Date date)
9. getFirstDayOfWeek(Date date)