Adding days, hours, calendar month or years to dates is a mutual chore inwards Java. java.util.Calendar tin move used to perform Date in addition to Time arithmetics inwards Java. Calendar course of written report non solely provides appointment manipulation only it besides back upward fourth dimension manipulation i.e. you lot tin add, subtract hours, minutes in addition to seconds from electrical flow time. Calendar course of written report automatically handles appointment transition or calendar month transition for representative if you lot inquire appointment after xxx days it volition render you lot appointment based on whether electrical flow calendar month is xxx or 31 days long. Same is truthful inwards instance of adding in addition to subtracting years, Calendar takes assist whether electrical flow or next twelvemonth is a leap year or not. For representative 2012 is a restrain twelvemonth in addition to it has Feb amongst 29 days, if you lot inquire Calendar 24-hour interval earlier 365 it volition render 24th July (assuming electrical flow appointment 23rd July) which shows it accept assist of restrain year. By the means at that spot are couplet of to a greater extent than appointment in addition to fourth dimension related articles e.g. How to abide by electrical flow appointment in addition to fourth dimension inwards Java in addition to How to convert Date to String inwards Java. If you lot haven’t read them already, It’s worth checking to know to a greater extent than almost Date in addition to Time inwards Java.
How to add together or subtract days, calendar month in addition to twelvemonth from appointment inwards Java
Calendar.DATE plain tin move used to add together or subtract dates inwards Java. Positive value passed into add() method volition add days into appointment spell negative values volition subtract days from appointment inwards Java. Similarly Calendar.MONTH tin move used to add together in addition to subtract months from appointment inwards Java. You tin purpose this to teach appointment after two months or earlier two months. Just drib dead on inwards hear that Calendar.MONTH start from zero. Same add() method tin move used to both add together or subtract months inwards Java. Once in ane lawsuit to a greater extent than divergence volition solely move on whether value is positive or negative. Calendar.YEAR tin move used to add together or subtract twelvemonth from electrical flow appointment inwards the same fashion nosotros added days in addition to calendar month into date.How to add together or subtract hour, minutes in addition to seconds from Time inwards Java
Calendar course of written report non solely provides Date information only besides gives Time related information. You tin teach hours, minutes in addition to seconds from java.util.Calendar instance. Similarly you lot tin purpose same add() method for adding or subtracting hours, minutes in addition to seconds from electrical flow fourth dimension inwards Java. Just ask to careful whether you lot are using Calendar.HOUR or Calendar.HOUR_OF_DAY because sometime stand upward for fourth dimension inwards AM in addition to PM spell later on stand upward for fourth dimension inwards 24 hours time. Calendar.MINUTES tin move used for adding or subtracting minutes from Date.
Important points related to Calendar course of written report inwards Java
1) Calendar has overloaded getInstance() method which tin render Calendar instance inwards either default timezone in addition to locale or specified timezone or locale.
2) Calendar has unlike fields to render specifics from Calendar similar Calendar.DATE, Calendar.MONTH, Calendar.YEAR etc you lot tin depository fiscal establishment lucifer Javadoc for total list.
3) Calendar.MONTH render naught for starting fourth dimension month, drib dead on inwards hear spell using value returned past times Calendar.get(Calendar.MONTH)
4) Calendar.HOUR_OF_DAY stand upward for fourth dimension inwards 24 hours format. Calendar besides back upward AM or PM format.
import java.util.Calendar;
import java.util.TimeZone;
/**
* Java programme to add, subtract dates, calendar month in addition to twelvemonth using Calendar inwards Java.
import java.util.TimeZone;
/**
* Java programme to add, subtract dates, calendar month in addition to twelvemonth using Calendar inwards Java.
* Apart from date, Calendar course of written report besides render fourth dimension related information in addition to can
* move used to add together in addition to subtract hours, minutes in addition to seconds from fourth dimension inwards Java.
*
* @author Javin Paul
*/
public class DateAndTimeArithmetic {
public static void main(String args[]){
//Java calendar inwards default timezone in addition to default locale
Calendar cal = Calendar.getInstance();
cal.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println("current date: " + getDate(cal));
//adding days into Date inwards Java
cal.add(Calendar.DATE, 2);
System.out.println("date after two days : " + getDate(cal));
//subtracting days from Date inwards Java
cal.add(Calendar.DATE, -2);
System.out.println("date earlier two days : " + getDate(cal));
//adding moths into Date
cal.add(Calendar.MONTH, 5);
System.out.println("date after v months : " + getDate(cal));
//subtracting months from Date
cal.add(Calendar.MONTH, -5);
System.out.println("date earlier v months : " + getDate(cal));
//adding twelvemonth into Date
cal.add(Calendar.YEAR, 5);
System.out.println("date after v years : " + getDate(cal));
//subtracting twelvemonth from Date
cal.add(Calendar.YEAR, -5);
System.out.println("date earlier v years : " + getDate(cal));
//date after 200 days from now, takes assist of how many days are inwards month
//for years calendar takes assist of restrain twelvemonth every bit well
cal.add(Calendar.DATE, 200);
System.out.println("date after 200 days from today : " + getDate(cal));
System.out.println("current fourth dimension inwards GMT: " + getTime(cal));
//adding hours into Date
cal.add(Calendar.HOUR_OF_DAY, 3);
System.out.println("Time after iii hours : " + getTime(cal));
//subtracting hours from Date time
cal.add(Calendar.HOUR_OF_DAY, -3);
System.out.println("Time earlier iii hours : " + getTime(cal));
//adding minutes into Date time
cal.add(Calendar.MINUTE, 3);
System.out.println("Time after iii minutes : " + getTime(cal));
//subtracting minutes from Date time
cal.add(Calendar.HOUR_OF_DAY, -3);
System.out.println("Time earlier iii minuets : " + getTime(cal));
}
/**
*
* @return electrical flow Date from Calendar inwards dd/MM/yyyy format
* adding 1 into calendar month because Calendar calendar month starts from zero
*/
public static String getDate(Calendar cal){
return "" + cal.get(Calendar.DATE) +"/" +
(cal.get(Calendar.MONTH)+1) + "/" + cal.get(Calendar.YEAR);
}
/**
*
* @return electrical flow Date from Calendar inwards HH:mm:SS format
*
* adding 1 into calendar month because Calendar calendar month starts from zero
*/
public static String getTime(Calendar cal){
return "" + cal.get(Calendar.HOUR_OF_DAY) +":" +
(cal.get(Calendar.MINUTE)) + ":" + cal.get(Calendar.SECOND);
}
}
Output:
electrical flow date: 23/7/2012
appointment after 2 days : 25/7/2012
appointment earlier 2 days : 23/7/2012
appointment after 5 months : 23/12/2012
appointment earlier 5 months : 23/7/2012
appointment after 5 years : 23/7/2017
appointment earlier 5 years : 23/7/2012
appointment after 200 days from today : 8/2/2013
electrical flow fourth dimension inwards GMT: 6:12:53
Time after 3 hours : 9:12:53
Time earlier 3 hours : 6:12:53
Time after 3 minutes : 6:15:53
Time earlier 3 minuets : 3:15:53
* @author Javin Paul
*/
public class DateAndTimeArithmetic {
public static void main(String args[]){
//Java calendar inwards default timezone in addition to default locale
Calendar cal = Calendar.getInstance();
cal.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println("current date: " + getDate(cal));
//adding days into Date inwards Java
cal.add(Calendar.DATE, 2);
System.out.println("date after two days : " + getDate(cal));
//subtracting days from Date inwards Java
cal.add(Calendar.DATE, -2);
System.out.println("date earlier two days : " + getDate(cal));
//adding moths into Date
cal.add(Calendar.MONTH, 5);
System.out.println("date after v months : " + getDate(cal));
//subtracting months from Date
cal.add(Calendar.MONTH, -5);
System.out.println("date earlier v months : " + getDate(cal));
//adding twelvemonth into Date
cal.add(Calendar.YEAR, 5);
System.out.println("date after v years : " + getDate(cal));
//subtracting twelvemonth from Date
cal.add(Calendar.YEAR, -5);
System.out.println("date earlier v years : " + getDate(cal));
//date after 200 days from now, takes assist of how many days are inwards month
//for years calendar takes assist of restrain twelvemonth every bit well
cal.add(Calendar.DATE, 200);
System.out.println("date after 200 days from today : " + getDate(cal));
System.out.println("current fourth dimension inwards GMT: " + getTime(cal));
//adding hours into Date
cal.add(Calendar.HOUR_OF_DAY, 3);
System.out.println("Time after iii hours : " + getTime(cal));
//subtracting hours from Date time
cal.add(Calendar.HOUR_OF_DAY, -3);
System.out.println("Time earlier iii hours : " + getTime(cal));
//adding minutes into Date time
cal.add(Calendar.MINUTE, 3);
System.out.println("Time after iii minutes : " + getTime(cal));
//subtracting minutes from Date time
cal.add(Calendar.HOUR_OF_DAY, -3);
System.out.println("Time earlier iii minuets : " + getTime(cal));
}
/**
*
* @return electrical flow Date from Calendar inwards dd/MM/yyyy format
* adding 1 into calendar month because Calendar calendar month starts from zero
*/
public static String getDate(Calendar cal){
return "" + cal.get(Calendar.DATE) +"/" +
(cal.get(Calendar.MONTH)+1) + "/" + cal.get(Calendar.YEAR);
}
/**
*
* @return electrical flow Date from Calendar inwards HH:mm:SS format
*
* adding 1 into calendar month because Calendar calendar month starts from zero
*/
public static String getTime(Calendar cal){
return "" + cal.get(Calendar.HOUR_OF_DAY) +":" +
(cal.get(Calendar.MINUTE)) + ":" + cal.get(Calendar.SECOND);
}
}
Output:
electrical flow date: 23/7/2012
appointment after 2 days : 25/7/2012
appointment earlier 2 days : 23/7/2012
appointment after 5 months : 23/12/2012
appointment earlier 5 months : 23/7/2012
appointment after 5 years : 23/7/2017
appointment earlier 5 years : 23/7/2012
appointment after 200 days from today : 8/2/2013
electrical flow fourth dimension inwards GMT: 6:12:53
Time after 3 hours : 9:12:53
Time earlier 3 hours : 6:12:53
Time after 3 minutes : 6:15:53
Time earlier 3 minuets : 3:15:53
That’s all on How to add together days, calendar month in addition to twelvemonth on Date inwards Java. We possess got besides seen how to add together hours, minutes in addition to seconds into fourth dimension using java.util.Calendar class. Two points which is worth remembering is that calendar month starts from naught in addition to fourth dimension tin move represented inwards either 24 hours format or AM-PM format.
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