I think this java class is easier to use and more reliable.
I found it in Iranian forum, Iranians use Jalali Calendar and call it "Shamsi" that means Solar calendar. this is the Java class:
package MyUtil;
import java.util.Calendar;
import java.util.GregorianCalendar;
/**
* Title: Calender Conversion class
* Description: Convert Iranian (Jalali), Julian, and Gregorian dates to
* each other
* Public Methods Summary:
* -----------------------
* JavaSource_Calendar();
* JavaSource_Calendar(int year, int month, int day);
* int getIranianYear();
* int getIranianMonth();
* int getIranianDay();
* int getGregorianYear();
* int getGregorianMonth();
* int getGregorianDay();
* int getJulianYear();
* int getJulianMonth();
* int getJulianDay();
* String getIranianDate();
* String getGregorianDate();
* String getJulianDate();
* String getWeekDayStr();
* String toString();
* int getDayOfWeek();
* void nextDay();
* void nextDay(int days);
* void previousDay();
* void previousDay(int days);
* void setIranianDate(int year, int month, int day);
* void setGregorianDate(int year, int month, int day);
* void setJulianDate(int year, int month, int day);
*/
public class CalendarTool {
/**
* JavaSource_Calendar:
* The default constructor uses the current Gregorian date to initialize the
* other private memebers of the class (Iranian and Julian dates).
*/
public CalendarTool()
{
Calendar calendar = new GregorianCalendar();
setGregorianDate(calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH)+1,
calendar.get(Calendar.DAY_OF_MONTH));
}
/**
* JavaSource_Calendar:
* This constructor receives a Gregorian date and initializes the other private
* members of the class accordingly.
* @param year int
* @param month int
* @param day int
*/
public CalendarTool(int year, int month, int day)
{
setGregorianDate(year,month,day);
}
/**
* getIranianYear:
* Returns the 'year' part of the Iranian date.
* @return int
*/
public int getIranianYear() {
return irYear;
}
/**
* getIranianMonth:
* Returns the 'month' part of the Iranian date.
* @return int
*/
public int getIranianMonth() {
return irMonth;
}
/**
* getIranianDay:
* Returns the 'day' part of the Iranian date.
* @return int
*/
public int getIranianDay() {
return irDay;
}
/**
* getGregorianYear:
* Returns the 'year' part of the Gregorian date.
* @return int
*/
public int getGregorianYear() {
return gYear;
}
/**
* getGregorianMonth:
* Returns the 'month' part of the Gregorian date.
* @return int
*/
public int getGregorianMonth() {
return gMonth;
}
/**
* getGregorianDay:
* Returns the 'day' part of the Gregorian date.
* @return int
*/
public int getGregorianDay() {
return gDay;
}
/**
* getJulianYear:
* Returns the 'year' part of the Julian date.
* @return int
*/
public int getJulianYear() {
return juYear;
}
/**
* getJulianMonth:
* Returns the 'month' part of the Julian date.
* @return int
*/
public int getJulianMonth() {
return juMonth;
}
/**
* getJulianDay()
* Returns the 'day' part of the Julian date.
* @return int
*/
public int getJulianDay() {
return juDay;
}
/**
* getIranianDate:
* Returns a string version of Iranian date
* @return String
*/
public String getIranianDate()
{
return (irYear+"/"+irMonth+"/"+irDay);
}
/**
* getGregorianDate:
* Returns a string version of Gregorian date
* @return String
*/
public String getGregorianDate()
{
return (gYear+"/"+gMonth+"/"+gDay);
}
/**
* getJulianDate:
* Returns a string version of Julian date
* @return String
*/
public String getJulianDate()
{
return (juYear+"/"+juMonth+"/"+juDay);
}
/**
* getWeekDayStr:
* Returns the week day name.
* @return String
*/
public String getWeekDayStr()
{
String weekDayStr[]={
"Monday",
"Tuesday",
"Wednesday",
"Thursday",
"Friday",
"Saturday",
"Sunday"};
return (weekDayStr[getDayOfWeek()]);
}
/**
* toString:
* Overrides the default toString() method to return all dates.
* @return String
*/
public String toString()
{
return (getWeekDayStr()+
", Gregorian:["+getGregorianDate()+
"], Julian:["+getJulianDate()+
"], Iranian:["+getIranianDate()+"]");
}
/**
* getDayOfWeek:
* Returns the week day number. Monday=0..Sunday=6;
* @return int
*/
public int getDayOfWeek()
{
return (JDN % 7);
}
/**
* nextDay:
* Go to next julian day number (JDN) and adjusts the other dates.
*/
public void nextDay()
{
JDN++;
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* nextDay:
* Overload the nextDay() method to accept the number of days to go ahead and
* adjusts the other dates accordingly.
* @param days int
*/
public void nextDay(int days)
{
JDN+=days;
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* previousDay:
* Go to previous julian day number (JDN) and adjusts the otehr dates.
*/
public void previousDay()
{
JDN--;
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* previousDay:
* Overload the previousDay() method to accept the number of days to go backward
* and adjusts the other dates accordingly.
* @param days int
*/
public void previousDay(int days)
{
JDN-=days;
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* setIranianDate:
* Sets the date according to the Iranian calendar and adjusts the other dates.
* @param year int
* @param month int
* @param day int
*/
public void setIranianDate(int year, int month, int day)
{
irYear =year;
irMonth = month;
irDay = day;
JDN = IranianDateToJDN();
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* setGregorianDate:
* Sets the date according to the Gregorian calendar and adjusts the other dates.
* @param year int
* @param month int
* @param day int
*/
public void setGregorianDate(int year, int month, int day)
{
gYear = year;
gMonth = month;
gDay = day;
JDN = gregorianDateToJDN(year,month,day);
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* setJulianDate:
* Sets the date according to the Julian calendar and adjusts the other dates.
* @param year int
* @param month int
* @param day int
*/
public void setJulianDate(int year, int month, int day)
{
juYear = year;
juMonth = month;
juDay = day;
JDN = julianDateToJDN(year,month,day);
JDNToIranian();
JDNToJulian();
JDNToGregorian();
}
/**
* IranianCalendar:
* This method determines if the Iranian (Jalali) year is leap (366-day long)
* or is the common year (365 days), and finds the day in March (Gregorian
* Calendar)of the first day of the Iranian year ('irYear').Iranian year (irYear)
* ranges from (-61 to 3177).This method will set the following private data
* members as follows:
* leap: Number of years since the last leap year (0 to 4)
* Gy: Gregorian year of the begining of Iranian year
* march: The March day of Farvardin the 1st (first day of jaYear)
*/
private void IranianCalendar()
{
// Iranian years starting the 33-year rule
int Breaks[]=
{-61, 9, 38, 199, 426, 686, 756, 818,1111,1181,
1210,1635,2060,2097,2192,2262,2324,2394,2456,3178} ;
int jm,N,leapJ,leapG,jp,j,jump;
gYear = irYear + 621;
leapJ = -14;
jp = Breaks[0];
// Find the limiting years for the Iranian year 'irYear'
j=1;
do{
jm=Breaks[j];
jump = jm-jp;
if (irYear >= jm)
{
leapJ += (jump / 33 * 8 + (jump % 33) / 4);
jp = jm;
}
j++;
} while ((j<20) && (irYear >= jm));
N = irYear - jp;
// Find the number of leap years from AD 621 to the begining of the current
// Iranian year in the Iranian (Jalali) calendar
leapJ += (N/33 * 8 + ((N % 33) +3)/4);
if ( ((jump % 33) == 4 ) && ((jump-N)==4))
leapJ++;
// And the same in the Gregorian date of Farvardin the first
leapG = gYear/4 - ((gYear /100 + 1) * 3 / 4) - 150;
march = 20 + leapJ - leapG;
// Find how many years have passed since the last leap year
if ( (jump - N) < 6 )
N = N - jump + ((jump + 4)/33 * 33);
leap = (((N+1) % 33)-1) % 4;
if (leap == -1)
leap = 4;
}
/**
* IsLeap:
* This method determines if the Iranian (Jalali) year is leap (366-day long)
* or is the common year (365 days), and finds the day in March (Gregorian
* Calendar)of the first day of the Iranian year ('irYear').Iranian year (irYear)
* ranges from (-61 to 3177).This method will set the following private data
* members as follows:
* leap: Number of years since the last leap year (0 to 4)
* Gy: Gregorian year of the begining of Iranian year
* march: The March day of Farvardin the 1st (first day of jaYear)
*/
public boolean IsLeap(int irYear1)
{
// Iranian years starting the 33-year rule
int Breaks[]=
{-61, 9, 38, 199, 426, 686, 756, 818,1111,1181,
1210,1635,2060,2097,2192,2262,2324,2394,2456,3178} ;
int jm,N,leapJ,leapG,jp,j,jump;
gYear = irYear1 + 621;
leapJ = -14;
jp = Breaks[0];
// Find the limiting years for the Iranian year 'irYear'
j=1;
do{
jm=Breaks[j];
jump = jm-jp;
if (irYear1 >= jm)
{
leapJ += (jump / 33 * 8 + (jump % 33) / 4);
jp = jm;
}
j++;
} while ((j<20) && (irYear1 >= jm));
N = irYear1 - jp;
// Find the number of leap years from AD 621 to the begining of the current
// Iranian year in the Iranian (Jalali) calendar
leapJ += (N/33 * 8 + ((N % 33) +3)/4);
if ( ((jump % 33) == 4 ) && ((jump-N)==4))
leapJ++;
// And the same in the Gregorian date of Farvardin the first
leapG = gYear/4 - ((gYear /100 + 1) * 3 / 4) - 150;
march = 20 + leapJ - leapG;
// Find how many years have passed since the last leap year
if ( (jump - N) < 6 )
N = N - jump + ((jump + 4)/33 * 33);
leap = (((N+1) % 33)-1) % 4;
if (leap == -1)
leap = 4;
if (leap==4 || leap==0)
return true;
else
return false;
}
/**
* IranianDateToJDN:
* Converts a date of the Iranian calendar to the Julian Day Number. It first
* invokes the 'IranianCalender' private method to convert the Iranian date to
* Gregorian date and then returns the Julian Day Number based on the Gregorian
* date. The Iranian date is obtained from 'irYear'(1-3100),'irMonth'(1-12) and
* 'irDay'(1-29/31).
* @return long (Julian Day Number)
*/
private int IranianDateToJDN()
{
IranianCalendar();
return (gregorianDateToJDN(gYear,3,march)+ (irMonth-1) * 31 - irMonth/7 * (irMonth-7) + irDay -1);
}
/**
* JDNToIranian:
* Converts the current value of 'JDN' Julian Day Number to a date in the
* Iranian calendar. The caller should make sure that the current value of
* 'JDN' is set correctly. This method first converts the JDN to Gregorian
* calendar and then to Iranian calendar.
*/
private void JDNToIranian()
{
JDNToGregorian();
irYear = gYear - 621;
IranianCalendar(); // This invocation will update 'leap' and 'march'
int JDN1F = gregorianDateToJDN(gYear,3,march);
int k = JDN - JDN1F;
if (k >= 0)
{
if (k <= 185)
{
irMonth = 1 + k/31;
irDay = (k % 31) + 1;
return;
}
else
k -= 186;
}
else
{
irYear--;
k += 179;
if (leap == 1)
k++;
}
irMonth = 7 + k/30;
irDay = (k % 30) + 1;
}
/**
* julianDateToJDN:
* Calculates the julian day number (JDN) from Julian calendar dates. This
* integer number corresponds to the noon of the date (i.e. 12 hours of
* Universal Time). This method was tested to be good (valid) since 1 March,
* -100100 (of both calendars) up to a few millions (10^6) years into the
* future. The algorithm is based on D.A.Hatcher, Q.Jl.R.Astron.Soc. 25(1984),
* 53-55 slightly modified by K.M. Borkowski, Post.Astron. 25(1987), 275-279.
* @param year int
* @param month int
* @param day int
* @return int
*/
private int julianDateToJDN(int year, int month, int day)
{
return (year + (month - 8) / 6 + 100100) * 1461/4 + (153 * ((month+9) % 12) + 2)/5 + day - 34840408;
}
/**
* JDNToJulian:
* Calculates Julian calendar dates from the julian day number (JDN) for the
* period since JDN=-34839655 (i.e. the year -100100 of both calendars) to
* some millions (10^6) years ahead of the present. The algorithm is based on
* D.A. Hatcher, Q.Jl.R.Astron.Soc. 25(1984), 53-55 slightly modified by K.M.
* Borkowski, Post.Astron. 25(1987), 275-279).
*/
private void JDNToJulian()
{
int j= 4 * JDN + 139361631;
int i= ((j % 1461)/4) * 5 + 308;
juDay = (i % 153) / 5 + 1;
juMonth = ((i/153) % 12) + 1;
juYear = j/1461 - 100100 + (8-juMonth)/6;
}
/**
* gergorianDateToJDN:
* Calculates the julian day number (JDN) from Gregorian calendar dates. This
* integer number corresponds to the noon of the date (i.e. 12 hours of
* Universal Time). This method was tested to be good (valid) since 1 March,
* -100100 (of both calendars) up to a few millions (10^6) years into the
* future. The algorithm is based on D.A.Hatcher, Q.Jl.R.Astron.Soc. 25(1984),
* 53-55 slightly modified by K.M. Borkowski, Post.Astron. 25(1987), 275-279.
* @param year int
* @param month int
* @param day int
* @return int
*/
private int gregorianDateToJDN(int year, int month, int day)
{
int jdn = (year + (month - 8) / 6 + 100100) * 1461/4 + (153 * ((month+9) % 12) + 2)/5 + day - 34840408;
jdn = jdn - (year + 100100+(month-8)/6)/100*3/4+752;
return (jdn);
}
/**
* JDNToGregorian:
* Calculates Gregorian calendar dates from the julian day number (JDN) for
* the period since JDN=-34839655 (i.e. the year -100100 of both calendars) to
* some millions (10^6) years ahead of the present. The algorithm is based on
* D.A. Hatcher, Q.Jl.R.Astron.Soc. 25(1984), 53-55 slightly modified by K.M.
* Borkowski, Post.Astron. 25(1987), 275-279).
*/
private void JDNToGregorian()
{
int j= 4 * JDN + 139361631;
j = j + (((((4* JDN +183187720)/146097)*3)/4)*4-3908);
int i= ((j % 1461)/4) * 5 + 308;
gDay = (i % 153) / 5 + 1;
gMonth = ((i/153) % 12) + 1;
gYear = j/1461 - 100100 + (8-gMonth)/6;
}
private int irYear; // Year part of a Iranian date
private int irMonth; // Month part of a Iranian date
private int irDay; // Day part of a Iranian date
private int gYear; // Year part of a Gregorian date
private int gMonth; // Month part of a Gregorian date
private int gDay; // Day part of a Gregorian date
private int juYear; // Year part of a Julian date
private int juMonth; // Month part of a Julian date
private int juDay; // Day part of a Julian date
private int leap; // Number of years since the last leap year (0 to 4)
private int JDN; // Julian Day Number
private int march; // The march day of Farvardin the first (First day of jaYear)
} // End of Class 'JavaSource_Calendar
You can easily set the Gregorian Day, Month and Year, then call "getIranianDate()" method to get the date in string format, just like the sample code below:
MyUtil.CalendarTool ct = new CalendarTool(2012,10,10);
System.out.println(ct.getIranianDate());
I hope it helps.
