Java Date Add addDate(Date date, String unit, int quantity)

Description

add date

License

Open Source License

Parameter

Parameter	Description
date	start date
unit	the unit for add
quantity	the quantity for add

Return

date

Declaration

public static Date addDate(Date date, String unit, int quantity) 

Method Source Code

//package com.java2s;

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

public class Main {
    /**/* w  w  w.  j  av a 2 s .c  o m*/
     * add date
     * 
     * @param date start date
     * @param unit the unit for add
     * @param quantity the quantity for add
     * @return date
     */
    public static Date addDate(Date date, String unit, int quantity) {
        if (unit.equalsIgnoreCase("Year")) {
            return addYear(date, quantity);
        }
        if (unit.equalsIgnoreCase("Month")) {
            return addMonth(date, quantity);
        }
        if (unit.equalsIgnoreCase("Week")) {
            return addWeek(date, quantity);
        }
        if (unit.equalsIgnoreCase("Day")) {
            return addDay(date, quantity);
        }
        if (unit.equalsIgnoreCase("Hour")) {
            return addHour(date, quantity);
        }
        if (unit.equalsIgnoreCase("Minute")) {
            return addMinute(date, quantity);
        }
        if (unit.equalsIgnoreCase("Second")) {
            return addSecond(date, quantity);
        }
        return null;
    }

    /**
     * <pre>
     * The calculation of the date of the increase or decrease the number of years after the date.
     * years is positive for Canada, is negative for Less
     * 
     * DateUtils.addYear(20120101,2) = 20140101
     * DateUtils.addYear(20120101,-2) = 20100101
     * </pre>
     * 
     * @param date target date
     * @param years variable number
     * @return Date
     */
    public static Date addYear(Date date, int years) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.YEAR, years);
        return c.getTime();
    }

    /**
     * <pre>
     * The calculation of the date of the increase or decrease the number of months after the date.
     * months is positive for Canada, is negative for Less
     * 
     * <code>
     * DateUtils.addMonth(1970-01-01, 1) = 1970-02-01
     * </code>
     * </pre>
     * 
     * @param date target date
     * @param months variable number
     * @return Date
     */
    public static Date addMonth(Date date, int months) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.MONTH, months);
        return c.getTime();
    }

    /**
     * <pre>
     * The calculation of the date of the increase or decrease the number of weeks after the date. 
     * weeks is positive for Canada, is negative for Less
     * 
     *  DateUtils.addWeek(1970-01-01, 1) = 1970-01-08
     * </pre>
     * 
     * @param date target date
     * @param weeks variable number
     * @return Date
     */
    public static Date addWeek(Date date, int weeks) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.WEEK_OF_MONTH, weeks);
        return c.getTime();
    }

    /**
     * <pre>
     * The calculation of the date of increase, reducing the number of days of the date. 
     * days is a positive number that when added, is negative for the reduction
     * 
     *  DateUtils.addDay(1970-01-01, 1) = 1970-01-02
     * </pre>
     * 
     * @param date target date
     * @param days variable number
     * @return Date
     */
    public static Date addDay(Date date, int days) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.DATE, days);
        return c.getTime();
    }

    /**
     * <pre>
     * The calculation of the date of increase or decrease the number of hours after the date. 
     * hours is positive for Canada, is negative for Less
     * 
     *  DateUtils.addHour(1970-01-01 10:00, 1) = 1970-01-01 11:00
     * </pre>
     * 
     * @param date target date
     * @param hours variable number
     * @return Date
     */
    public static Date addHour(Date date, int hours) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.HOUR, hours);
        return c.getTime();
    }

    /**
     * <pre>
     * The calculation of the date of increase or decrease the number of minutes later date. 
     * minutes is positive for Canada, is negative for Less
     * 
     *  DateUtils.addMinute(1970-01-01 10:00, 1) = 1970-01-01 10:01
     * </pre>
     * 
     * @param date target date
     * @param minutes variable number
     * @return Date
     */
    public static Date addMinute(Date date, int minutes) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.MINUTE, minutes);
        return c.getTime();
    }

    /**
     * <pre>
     * Increase or reduce the number of seconds after the date of calculation date 
     * when seconds is a positive number is added as a negative number is less.
     * 
     *  DateUtils.addSecond(1970-01-01 10:00:00, 1) = 1970-01-01 10:00:01
     * </pre>
     * 
     * @param date target date
     * @param seconds variable number
     * @return Date
     */
    public static Date addSecond(Date date, int seconds) {
        if (date == null) {
            return null;
        }
        Calendar c = getCalendar(date);
        c.add(Calendar.SECOND, seconds);
        return c.getTime();
    }

    /**
     * get GregorianCalendar.
     * 
     * @return Calendar,GregorianCalendar.
     */
    public static Calendar getCalendar() {
        return new GregorianCalendar();
    }

    /**
     * get GregorianCalendar with given date.
     * 
     * @param date Date.
     * @return Calendar, GregorianCalendar.
     */
    public static Calendar getCalendar(Date date) {
        Calendar calendar = getCalendar();
        calendar.setTime(date);
        return calendar;
    }
}

Related

1. addDate(Date date, int amount, int type)
2. addDate(Date date, int field, int add)
3. addDate(Date date, int k)
4. addDate(Date date, int noOfDays)
5. addDate(Date date, int years, int months, int days)
6. addDate(int field, int amount)
7. addDate(java.util.Date date, int day)
8. addDate(String date)
9. addDate(String date, int amount)