CODEWITHSUNDEEP
javacalendar
user3239782
user3239782

Reputation: 87

Calendar Class problems

I am having problems with the Calendar Class.

Calendar cal = Calendar.getInstance ();

int iYear  = cal.get (Calendar.YEAR);         // get the current year

int iMonth = cal.get (Calendar.MONTH);        // month...

int iDay   = cal.get (Calendar.); // current day in the month

This... No Workie!! :-(

I used the debugger and found that the YEAR and the DAY_OF_MONTH are correct, however, the MONTH is 1 (January) when it SHOULD BE 2 (February).

Here is where it gets even more WEIRD:

I then tried cal.clear ();

followed by cal.set (2014, 2, 27); // Today's Date - Feb 27, 2014

and the month was still 1 (i.e. January)

I set the date to days in January, (2014, 1, 1), (2014, 1, 16),etc It correctly gave me a 1 for the month

After reading and trying many things (and pulling my hair out..) I set it to a date in the future, my Birthday (2014, 5, 23) and other days. For those dates, Month was correctly set to 5 (May)

Upvotes: 1

Views: 336

Answers (6)

Basil Bourque
Basil Bourque

Reputation: 340070

tl;dr

LocalDate.now()
         .getYear()

java.time

The modern approach uses the industry-leading java.time classes.

LocalDate

The LocalDate class represents a date-only value without time-of-day and without time zone.

A time zone is crucial in determining a date. For any given moment, the date varies around the globe by zone. For example, a few minutes after midnight in Paris France is a new day while still “yesterday” in Montréal Québec.

If no time zone is specified, the JVM implicitly applies its current default time zone. That default may change at any moment, so your results may vary. Better to specify your desired/expected time zone explicitly as an argument.

Specify a proper time zone name in the format of continent/region, such as America/Montreal, Africa/Casablanca, or Pacific/Auckland. Never use the 3-4 letter abbreviation such as EST or IST as they are not true time zones, not standardized, and not even unique(!). 

ZoneId z = ZoneId.of( "America/Montreal" ) ;  
LocalDate today = LocalDate.now( z ) ;

If you want to use the JVM’s current default time zone, ask for it and pass as an argument. If omitted, the JVM’s current default is applied implicitly. Better to be explicit.

ZoneId z = ZoneId.systemDefault() ;  // Get JVM’s current default time zone.

Or specify a date. You may set the month by a number, with sane numbering 1-12 for January-December. 

LocalDate ld = LocalDate.of( 1986 , 2 , 23 ) ;  // Years use sane direct numbering (1986 means year 1986). Months use sane numbering, 1-12 for January-December.

Or, better, use the Month enum objects pre-defined, one for each month of the year. Tip: Use these Month objects throughout your codebase rather than a mere integer number to make your code more self-documenting, ensure valid values, and provide type-safety.

LocalDate ld = LocalDate.of( 1986 , Month.FEBRUARY , 23 ) ;

Parts

Interrogate for the parts as needed.

int dayOfMonth = ld.getDayOfMonth() ;
int month = ld.getMonthValue() ;
int year = ld.getYear() ;

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

Where to obtain the java.time classes?

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

Upvotes: 1

Solution
Solution

Reputation: 602

Please see the description provided for MONTH Constant in Calendar Class.

Calendar.MONTH

public static final int MONTH

Field number for get and set indicating the month. This is a calendar-specific value. The first month of the year in the Gregorian and Julian calendars is JANUARY which is 0; the last depends on the number of months in a year.

So if you want to set the date in calendar than use below code snippet.

cal.set(2014, Calendar.FEBRUARY, 28);

I think it will help you.

Upvotes: 1

Rahul
Rahul

Reputation: 3519

In Calender class Jan as constant int is 0 , Feb is 1 ... .month constant int value is from 0,1,2..

Upvotes: 0

Rajshri
Rajshri

Reputation: 4153

Let try this simple program:

import java.util.Calendar;
class CalendarExample {
public static void main(String args[]) {

Calendar calendar = Calendar.getInstance();
System.out.println("Current Date : " + calendar.get(Calendar.DATE));
System.out.println("Current Month : " + calendar.get(Calendar.MONTH));
System.out.println("Current Year : " + calendar.get(Calendar.YEAR));
System.out.print("Current Time : ");
System.out.print(calendar.get(Calendar.HOUR) + ":");
System.out.print(calendar.get(Calendar.MINUTE) + ":");
System.out.print(calendar.get(Calendar.SECOND));
}
}

You get the o/p:

Current Date : 28
Current Month : 1
Current Year : 2014
Current Time : 11:18:3

Upvotes: 0

user180100
user180100

Reputation:

use constants in Calendar for month: Calendar.JANUARY etc

For example:

cal.set(2014, Calendar.FEBRUARY, 27);

Upvotes: 1

ntalbs
ntalbs

Reputation: 29458

Month in Calendar begins at 0, which means 0 is January, 1 is February, etc.

Java Date and Time API sucks. Use Joda-Time instead.

Upvotes: 1

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