Java Day of Month getLastDayOfMonth(java.util.Date date)

Description

getLastDayOfMonth: returns the last day of the given dates month

License

Apache License

Parameter

Parameter	Description
date	any day

Return

Date with no time {talendTypes} Date {Category} TimestampUtil {param} Date date: any day. {example} getLastDayOfMonth(date).

Declaration

public static java.util.Date getLastDayOfMonth(java.util.Date date)

Method Source Code

//package com.java2s;
/**//from ww  w.  ja v  a 2 s .co  m
 * Copyright 2015 Jan Lolling jan.lolling@gmail.com
 * 
 * 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.Calendar;

import java.util.Locale;

public class Main {
    /**
     * getLastDayOfMonth: returns the last day of the given dates month
     * @param date any day
     * @return Date with no time
     * 
     * {talendTypes} Date
     * 
     * {Category} TimestampUtil
     * 
     * {param} Date date: any day.
     * 
     * {example} getLastDayOfMonth(date).
     */
    public static java.util.Date getLastDayOfMonth(java.util.Date date) {
        date = addMonths(date, 1);
        return addDays(getFirstDayOfMonth(date), -1);
    }

    /**
     * addMonths: returns date + given months
     * @param today any day
     * @param monthsToAdd difference in months
     * @return Date with UTC time
     * 
     * {talendTypes} Date
     * 
     * {Category} TimestampUtil
     * 
     * {param} date today: any day.
     * 
     * {param} int month: months to be added. (-1 for yesterday)
     * 
     * {example} addDays(today, monthsToAdd).
     */
    public static java.util.Date addMonths(java.util.Date today,
            int monthsToAdd) {
        if (today != null) {
            java.util.Calendar c = java.util.Calendar.getInstance();
            c.setTime(today);
            c.add(Calendar.MONTH, monthsToAdd);
            return c.getTime();
        } else {
            return null;
        }
    }

    /**
     * addDays: returns date of yesterday
     * @param today any day
     * @param daysToAdd difference in days
     * @return Date with UTC time
     * 
     * {talendTypes} Date
     * 
     * {Category} TimestampUtil
     * 
     * {param} date today: any day.
     * 
     * {param} long day: days to be added. (-1 for yesterday)
     * 
     * {example} addDays(today, daysToAdd).
     */
    public static java.util.Date addDays(java.util.Date today,
            long daysToAdd) {
        if (today != null) {
            return new java.util.Date(today.getTime()
                    + (1000 * 60 * 60 * 24 * daysToAdd));
        } else {
            return null;
        }
    }

    /**
     * addDays: returns the integer as date
     * 
     * {talendTypes} String
     * 
     * {Category} TimestampUtil
     * 
     * {param} Integer(dateAsInt) dateAsInt : 
     * {param} Integer(daysToAdd) daysToAdd : 
     * 
     * {example} addDays(dateAsInt, daysToAdd) # 20150403
     */
    public static Integer addDays(Integer dateAsInt, Integer daysToAdd) {
        if (dateAsInt != null) {
            java.util.Calendar c = java.util.Calendar.getInstance();
            // cut time
            c.set(java.util.Calendar.MINUTE, 0);
            c.set(java.util.Calendar.SECOND, 0);
            c.set(java.util.Calendar.MILLISECOND, 0);
            c.set(java.util.Calendar.HOUR_OF_DAY, 0);
            int year = dateAsInt / 10000;
            int monthDay = (dateAsInt - (year * 10000));
            int month = monthDay / 100;
            int day = monthDay % 100;
            c.set(Calendar.YEAR, year);
            c.set(Calendar.MONTH, month - 1);
            c.set(Calendar.DAY_OF_MONTH, day);
            c.add(Calendar.DAY_OF_YEAR, daysToAdd);
            return getDateAsInt(c.getTime());
        } else {
            return null;
        }
    }

    /**
     * getFirstDayOfMonth: returns the first day of the given dates month
     * @param date any day
     * @return Date with no time
     * 
     * {talendTypes} Date
     * 
     * {Category} TimestampUtil
     * 
     * {param} Date date: any day.
     * 
     * {example} getFirstDayOfMonth(date).
     */
    public static java.util.Date getFirstDayOfMonth(java.util.Date date) {
        date = truncateToDay(date);
        if (date != null) {
            java.util.Calendar c = java.util.Calendar
                    .getInstance(Locale.GERMANY);
            c.setTime(date);
            c.set(Calendar.DAY_OF_MONTH, 1);
            return c.getTime();
        } else {
            return null;
        }
    }

    /**
     * getDateAsId: returns the current day as integer
     * 
     * {talendTypes} String
     * 
     * {Category} TimestampUtil
     * 
     * {param} Date(date) date : date to format
     * 
     * {example} getDateAsInt(date) # 20150403
     */
    public static Integer getDateAsInt(java.util.Date date) {
        if (date != null) {
            java.util.Calendar c = java.util.Calendar.getInstance();
            c.setTime(date);
            // cut time
            c.set(java.util.Calendar.MINUTE, 0);
            c.set(java.util.Calendar.SECOND, 0);
            c.set(java.util.Calendar.MILLISECOND, 0);
            c.set(java.util.Calendar.HOUR_OF_DAY, 0);
            int id = c.get(Calendar.YEAR) * 10000;
            id = id + (c.get(Calendar.MONTH) + 1) * 100;
            id = id + c.get(Calendar.DAY_OF_MONTH);
            return id;
        } else {
            return null;
        }
    }

    /**
     * truncateToDay: returns the start of the given day.
     * 
     * {Category} TimestampUtil
     * 
     * {talendTypes} Date
     * 
     * {param} Date() day: any day.
     * 
     * {example} truncateToDay(TalendDate.getCurentDate()).
     */
    public static java.util.Date truncateToDay(java.util.Date timestamp) {
        if (timestamp == null)
            return null;
        java.util.Calendar c = java.util.Calendar.getInstance();
        c.setTime(timestamp);
        // cut time
        c.set(java.util.Calendar.MINUTE, 0);
        c.set(java.util.Calendar.SECOND, 0);
        c.set(java.util.Calendar.MILLISECOND, 0);
        c.set(java.util.Calendar.HOUR_OF_DAY, 0);
        return c.getTime();
    }
}