shamsi / Jalali Calender in Android with string parameters

Question

i'm using this algorithm for changing Calender date to Persian calender. here it's work fine but: when i want to create a new constructor for getting parameters and change a String to Persian date, like change "2012/3/6" to Persian (instead of using a Internal date) i have a very odd problem and mount mismatches by one point. so when expect 1392/9/4 the algorithm shows 1392/8/4.

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

import android.net.ParseException;
import android.util.Log;

public class ShamsiCalleder {


        private class SolarCalendar {

            public String strWeekDay = "";
            public String strMonth = "";

            int date;
            int month;
            int year;

            public SolarCalendar(String str)
            {

                //SimpleDateFormat postFormater = new SimpleDateFormat("MMMM dd, yyyy"); 

                //String newDateStr = postFormater.format(dateObj); 



                // for converting input date
                Date MiladiDate = null;
                SimpleDateFormat  format = new SimpleDateFormat("yyyy/MM/dd");  
                try {  
                    MiladiDate = format.parse(str);  
                    System.out.println(date);  

                } catch (java.text.ParseException e) {

                    e.printStackTrace();
                }


                calcSolarCalendar(MiladiDate);
            }



            public SolarCalendar()
            {
                Date MiladiDate = new Date();
                Log.i("PRS", "from solarcalender="+MiladiDate);
                calcSolarCalendar(MiladiDate);
            }

            public SolarCalendar(Date MiladiDate)
            {
                calcSolarCalendar(MiladiDate);
            }

            private void calcSolarCalendar(Date MiladiDate) {

                int ld;

                int miladiYear = MiladiDate.getYear() + 1900;
                int miladiMonth = MiladiDate.getMonth() + 1;
                int miladiDate = MiladiDate.getDate();
                int WeekDay = MiladiDate.getDay();

                int[] buf1 = new int[12];
                int[] buf2 = new int[12];

                buf1[0] = 0;
                buf1[1] = 31;
                buf1[2] = 59;
                buf1[3] = 90;
                buf1[4] = 120;
                buf1[5] = 151;
                buf1[6] = 181;
                buf1[7] = 212;
                buf1[8] = 243;
                buf1[9] = 273;
                buf1[10] = 304;
                buf1[11] = 334;

                buf2[0] = 0;
                buf2[1] = 31;
                buf2[2] = 60;
                buf2[3] = 91;
                buf2[4] = 121;
                buf2[5] = 152;
                buf2[6] = 182;
                buf2[7] = 213;
                buf2[8] = 244;
                buf2[9] = 274;
                buf2[10] = 305;
                buf2[11] = 335;

                if ((miladiYear % 4) != 0) {
                    date = buf1[miladiMonth - 1] + miladiDate;

                    if (date > 79) {
                        date = date - 79;
                        if (date <= 186) {
                            switch (date % 31) {
                            case 0:
                                month = date / 31;
                                date = 31;
                                break;
                            default:
                                month = (date / 31) + 1;
                                date = (date % 31);
                                break;
                            }
                            year = miladiYear - 621;
                        } else {
                            date = date - 186;

                            switch (date % 30) {
                            case 0:
                                month = (date / 30) + 6;
                                date = 30;
                                break;
                            default:
                                month = (date / 30) + 7;
                                date = (date % 30);
                                break;
                            }
                            year = miladiYear - 621;
                        }
                    } else {
                        if ((miladiYear > 1996) && (miladiYear % 4) == 1) {
                            ld = 11;
                        } else {
                            ld = 10;
                        }
                        date = date + ld;

                        switch (date % 30) {
                        case 0:
                            month = (date / 30) + 9;
                            date = 30;
                            break;
                        default:
                            month = (date / 30) + 10;
                            date = (date % 30);
                            break;
                        }
                        year = miladiYear - 622;
                    }
                } else {
                    date = buf2[miladiMonth - 1] + miladiDate;

                    if (miladiYear >= 1996) {
                        ld = 79;
                    } else {
                        ld = 80;
                    }
                    if (date > ld) {
                        date = date - ld;

                        if (date <= 186) {
                            switch (date % 31) {
                            case 0:
                                month = (date / 31);
                                date = 31;
                                break;
                            default:
                                month = (date / 31) + 1;
                                date = (date % 31);
                                break;
                            }
                            year = miladiYear - 621;
                        } else {
                            date = date - 186;

                            switch (date % 30) {
                            case 0:
                                month = (date / 30) + 6;
                                date = 30;
                                break;
                            default:
                                month = (date / 30) + 7;
                                date = (date % 30);
                                break;
                            }
                            year = miladiYear - 621;
                        }
                    }

                    else {
                        date = date + 10;

                        switch (date % 30) {
                        case 0:
                            month = (date / 30) + 9;
                            date = 30;
                            break;
                        default:
                            month = (date / 30) + 10;
                            date = (date % 30);
                            break;
                        }
                        year = miladiYear - 622;
                    }

                }

                switch (month) {
                case 1:
                    strMonth = "�روردين";
                    break;
                case 2:
                    strMonth = "ارديبهشت";
                    break;
                case 3:
                    strMonth = "خرداد";
                    break;
                case 4:
                    strMonth = "تير";
                    break;
                case 5:
                    strMonth = "مرداد";
                    break;
                case 6:
                    strMonth = "شهريور";
                    break;
                case 7:
                    strMonth = "مهر";
                    break;
                case 8:
                    strMonth = "آبان";
                    break;
                case 9:
                    strMonth = "آذر";
                    break;
                case 10:
                    strMonth = "دي";
                    break;
                case 11:
                    strMonth = "بهمن";
                    break;
                case 12:
                    strMonth = "اس�ند";
                    break;
                }

                switch (WeekDay) {

                case 0:
                    strWeekDay = "يکشنبه";
                    break;
                case 1:
                    strWeekDay = "دوشنبه";
                    break;
                case 2:
                    strWeekDay = "سه شنبه";
                    break;
                case 3:
                    strWeekDay = "چهارشنبه";
                    break;
                case 4:
                    strWeekDay = "پنج شنبه";
                    break;
                case 5:
                    strWeekDay = "جمعه";
                    break;
                case 6:
                    strWeekDay = "شنبه";
                    break;
                }

            }

        }




        public static String getCurrentShamsidate() {
            Locale loc = new Locale("en_US");
            ShamsiCalleder shamsi = new ShamsiCalleder();
            SolarCalendar sc = shamsi.new SolarCalendar();
            return String.valueOf(sc.year) + "/" + String.format(loc, "%02d",
                    sc.month) + "/" + String.format(loc, "%02d", sc.date);
        }
        public static String getCurrentShamsidate(String str) {
            Locale loc = new Locale("en_US");
            ShamsiCalleder shamsi = new ShamsiCalleder();
            SolarCalendar sc = shamsi.new SolarCalendar(str);
            Log.i("PRS", "mointh is="+sc.month);
            return String.valueOf(sc.year) + "/" + String.format(loc, "%02d",
                    sc.month) + "/" + String.format(loc, "%02d", sc.date);
        }

so when i call: ShamsiCalleder.getCurrentShamsidate()

it's returns 1392/10/4 ( it's today and just right!)

and when i call ( today): ShamsiCalleder.getCurrentShamsidate("2013/12/25")

it's returns 1392/9/4

i hope some one help me on this. with regards.

Answer 1

ok i finally find the source of this problem.

i used to use this code for get a current date:

Calendar c = Calendar.getInstance(); 
int day = c.get(Calendar.DATE);
int mounth = c.get(Calendar.MONTH);
int year = c.get(Calendar.YEAR);

but i find out that the Months are Indexed from 0. so when it returns 11 it means that Dec.

so I changed code to this:

Calendar c = Calendar.getInstance(); 
int day = c.get(Calendar.DATE);
int mounth = c.get(Calendar.MONTH)+1;
int year = c.get(Calendar.YEAR);

thank to all my friends.

Answer 2

you can use this method like this :

public static String getPersianDate(Date d) {
    GregorianCalendar gc = new GregorianCalendar();
    gc.setTime(d);
    int year = gc.get(Calendar.YEAR);
    return getPersianDate(year, (gc.get(Calendar.MONTH)) + 1,
            gc.get(Calendar.DAY_OF_MONTH));
}

I hope it can help you