public class DateUtil { private boolean isItALeapYear = false; private int holidaysWorked; private int workDaysWorked; public boolean checkGregorianDate(String inDate) { String day, month, year; int _day, _month, _year; if (inDate.length() == 8) { day = inDate.charAt(6) + "" + inDate.charAt(7); month = inDate.charAt(4) + "" + inDate.charAt(5); year = inDate.charAt(0) + "" + inDate.charAt(1) + "" + inDate.charAt(2) + "" + inDate.charAt(3); _day = getValueOrNegativeOneForIntegers(day); _month = getValueOrNegativeOneForIntegers(month); _year = getValueOrNegativeOneForIntegers(year); } else { println("Enter a correct date EX(yyyy/mm/yy --> 03 07 2000) 8 CHARACTERS"); return false; } if (_day < 1 || _month < 1 || _month > 12 || _year < 1) { println("Enter an integer that works please, Thank you!"); return false; } if (!doesDayFitInMonth(_day, _month, _year)) { return false; } println("Your date is good!"); return true; } public int getWorkDaysWorked() { return workDaysWorked; } public int getHolidaysWorked() { return holidaysWorked; } public void daysTypeCount(String startWork, String endWork, String startHoliday, String endHoliday) { int startDay = getValueOrNegativeOneForIntegers(startWork.charAt(6) + "" + startWork.charAt(7)); int endDay = getValueOrNegativeOneForIntegers(endWork.charAt(6) + "" + endWork.charAt(7)); int startMonth = getValueOrNegativeOneForIntegers(startWork.charAt(4) + "" + startWork.charAt(5)); int endMonth = getValueOrNegativeOneForIntegers(endWork.charAt(4) + "" + endWork.charAt(5)); int startYear = getValueOrNegativeOneForIntegers(startWork.charAt(0) + "" + startWork.charAt(1) + "" + startWork.charAt(2) + "" + startWork.charAt(3)); int endYear = getValueOrNegativeOneForIntegers(endWork.charAt(0) + "" + endWork.charAt(1) + "" + endWork.charAt(2) + "" + endWork.charAt(3)); int startDayHoliday = getValueOrNegativeOneForIntegers(startHoliday.charAt(6) + "" + startHoliday.charAt(7)); int endDayHoliday = getValueOrNegativeOneForIntegers(endHoliday.charAt(6) + "" + endHoliday.charAt(7)); int startMonthHoliday = getValueOrNegativeOneForIntegers(startHoliday.charAt(4) + "" + startHoliday.charAt(5)); int endMonthHoliday = getValueOrNegativeOneForIntegers(endHoliday.charAt(4) + "" + endHoliday.charAt(5)); int startYearHoliday = getValueOrNegativeOneForIntegers(startHoliday.charAt(0) + "" + startHoliday.charAt(1) + "" + startHoliday.charAt(2) + "" + startHoliday.charAt(3)); int endYearHoliday = getValueOrNegativeOneForIntegers(endHoliday.charAt(0) + "" + endHoliday.charAt(1) + "" + endHoliday.charAt(2) + "" + endHoliday.charAt(3)); //Todo: add if one of the dates are equal and the other is not if (endYearHoliday < startYear || startYearHoliday < endYear) {//days worked aren't aligned with holidays setHolidaysWorked("0"); setWorkDaysWorked(daysDiff(startWork, endWork)); } else if (startYear > startYearHoliday && endYear < endYearHoliday) {//he worked through out the holiday setHolidaysWorked(daysDiff(startWork, endWork)); setWorkDaysWorked("0");//days worked on normal work days == 0; } else if (startYear < startYearHoliday && endYear > endYearHoliday) { setHolidaysWorked(daysDiff(startHoliday, endHoliday)); workDaysWorked = Math.abs(holidaysWorked - getValueOrNegativeOneForIntegers(daysDiff(startWork, endHoliday))); } else if (startYear > startYearHoliday && endYear > endYearHoliday) { holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, endHoliday)); workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff(endHoliday, endWork)); } else if (startYear < startYearHoliday && endYear < endYearHoliday) { holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startHoliday, endWork)); workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, startHoliday)); } else if (startYear == startYearHoliday && endYear < endYearHoliday) { holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, endWork)); workDaysWorked = 0; } else if (startYear == startYearHoliday && endYear > endYearHoliday) { holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, endHoliday)); workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff(endHoliday, endWork)); } else if (endYear == endYearHoliday && startYear < startYearHoliday) { workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, startHoliday)); holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startHoliday, endWork)); } else if (endYear == endYearHoliday && startYear > startYearHoliday) { workDaysWorked = 0; holidaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, endWork)); } else if (startYear == startYearHoliday && endYear == endYearHoliday) { if (startMonth > endMonthHoliday || startMonthHoliday > endMonth) { holidaysWorked = 0; workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff(startWork, endWork)); } else if (startMonth < startMonthHoliday && endMonth < endMonthHoliday) { workDaysWorked = Math.abs((monthToDays(startMonthHoliday) + startDayHoliday) - (monthToDays(startMonth) + startDay)); holidaysWorked = Math.abs((monthToDays(endMonth) + endDay) - (monthToDays(startMonthHoliday) + startDayHoliday)); } else if (startMonth > startMonthHoliday && endMonth > endMonthHoliday) { holidaysWorked = Math.abs((monthToDays(endMonthHoliday) + endDayHoliday) - (monthToDays(startMonth) + startDay)); workDaysWorked = Math.abs((monthToDays(endMonth) + endDay) - (monthToDays(endMonthHoliday) + endDayHoliday)); } else if (startMonth < startMonthHoliday && endMonth > endMonthHoliday) { holidaysWorked = Math.abs((monthToDays(startMonthHoliday) + startDayHoliday) - (monthToDays(startMonth) + startDay)); workDaysWorked = Math.abs((monthToDays(startMonth) + startDay + monthToDays(endMonth) + endDay) - holidaysWorked); } else if (startMonth > startMonthHoliday && endMonth < endMonthHoliday) { holidaysWorked = (monthToDays(endMonth) + endDay) - (monthToDays(startMonth) + startDay); workDaysWorked = 0; } else if (startMonth == startMonthHoliday && endMonth < endMonthHoliday) { workDaysWorked = 0; holidaysWorked = Math.abs((monthToDays(endMonth) + endDay)); } else if (startMonth == startMonthHoliday && endMonth > endMonthHoliday) {//todo here workDaysWorked = (monthToDays(endMonthHoliday) + endDayHoliday); holidaysWorked = Math.abs((monthToDays(endMonth) + endDay) - (monthToDays(endMonthHoliday) + endDayHoliday)); } else if (startMonth > startMonthHoliday && endMonth == endMonthHoliday) { holidaysWorked = ((monthToDays(endMonth) + endDay) - monthToDays(startMonth) + startDay); workDaysWorked = 0; } else if (startMonth < startMonthHoliday && endMonth == endMonthHoliday) { workDaysWorked = Math.abs((monthToDays(startMonth) + startDay) - monthToDays(startMonthHoliday) + startDayHoliday); holidaysWorked = Math.abs(holidaysWorked - (monthToDays(endMonth) + endDay)); } else if (startMonth == startMonthHoliday && endMonth == endMonthHoliday) { if (endDay < startDayHoliday || endDayHoliday < startDay) { workDaysWorked = (endDay - startDay) + 1; holidaysWorked = 0; } else if (startDay == startDayHoliday && endDay == endDayHoliday) { workDaysWorked = 0; holidaysWorked = (endDay - startDay) + 1; } else if (startDay < startDayHoliday && endDay < endDayHoliday) { workDaysWorked = Math.abs((startDayHoliday - startDay)) + 1; holidaysWorked = Math.abs((endDay - startDayHoliday)) + 1; } else if (startDay > startDayHoliday && endDay > endDayHoliday) { workDaysWorked = Math.abs((endDay - endDayHoliday) + 1); holidaysWorked = Math.abs((endDayHoliday - startDay) + 1); } else if (startDay < startDayHoliday && endDay > endDayHoliday) { holidaysWorked = (endDayHoliday - startDayHoliday) + 1; workDaysWorked = (endDay - startDay) - holidaysWorked; } else if (startDay > startDayHoliday && endDay < endDayHoliday) { holidaysWorked = (endDay - startDay) + 1; workDaysWorked = 0; } else if (startDay == startDayHoliday && endDay < endDayHoliday) { workDaysWorked = 0; holidaysWorked = Math.abs(endDay - startDay) +1; }else if (startDay == startDayHoliday && endDay > endDayHoliday) { holidaysWorked = Math.abs(endDayHoliday - startDay) +1; workDaysWorked = Math.abs(endDay - holidaysWorked); }else if (endDayHoliday == endDay && startDay > startDayHoliday) { holidaysWorked = Math.abs(endDayHoliday - startDay) +1; workDaysWorked = 0; }else if (endDayHoliday == endDay && startDay < startDayHoliday) { workDaysWorked = Math.abs(startDayHoliday - startDay)+1; holidaysWorked = Math.abs(endDayHoliday - startDayHoliday) +1; } } } } private void setWorkDaysWorked(String daysDiff) { workDaysWorked = getValueOrNegativeOneForIntegers(daysDiff); } private void setHolidaysWorked(String days) { holidaysWorked = getValueOrNegativeOneForIntegers(days); } public boolean checkJulianDate(String inDate) { String day, year; int _day; if (inDate.length() == 7) { day = inDate.charAt(4) + "" + inDate.charAt(5) + "" + inDate.charAt(6); year = inDate.charAt(0) + "" + inDate.charAt(1) + "" + inDate.charAt(2) + "" + inDate.charAt(3); _day = getValueOrNegativeOneForIntegers(day); } else { println("7 digits please"); return false; } if (_day < 1 || _day > 365 && !getIsItALeapYear(getValueOrNegativeOneForIntegers(year)) || year.length() != 4) { println("Enter an integer that works please, Thank you!"); return false; } else if (_day < 1 || _day > 366 && getIsItALeapYear(getValueOrNegativeOneForIntegers(year)) || year.length() != 4) { println("Enter an integer that works please, Thank you!"); return false; } println("Your Julian date is good!"); return true; } private boolean doesDayFitInMonth(int day, int month, int year) { isItALeapYear = getIsItALeapYear(year); switch (month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: if (day > 31) { return false; } break;//All months with 31 days case 2://February if (isItALeapYear && day > 29) { return false; } else if (!isItALeapYear && day > 28) { return false; } break; case 4: case 6: case 9: case 11: if (day > 30) { return false; } break;//All months with 30 days } return true; } public String gregorianDateToJulianDate(String inDate) { String day = inDate.charAt(6) + "" + inDate.charAt(7); String month = inDate.charAt(4) + "" + inDate.charAt(5); String year = inDate.charAt(0) + "" + inDate.charAt(1) + "" + inDate.charAt(2) + "" + inDate.charAt(3); int _day = getValueOrNegativeOneForIntegers(day); int _month = getValueOrNegativeOneForIntegers(month); int totalDays = _day + monthToDays(_month); String julianDate; if (totalDays < 100 && totalDays > 9) { julianDate = year + "0" + totalDays + ""; } else if (totalDays < 10) { julianDate = year + "00" + totalDays + ""; } else { julianDate = year + "" + totalDays + ""; } return julianDate; } public String julianDateToGregorianDate(String inDate) { int month = 0; String year = inDate.charAt(0) + "" + inDate.charAt(1) + "" + inDate.charAt(2) + "" + inDate.charAt(3); String day = inDate.charAt(4) + "" + inDate.charAt(5) + "" + inDate.charAt(6); String gregorianDate; int _day = getValueOrNegativeOneForIntegers(day); isItALeapYear = getIsItALeapYear(getValueOrNegativeOneForIntegers(year)); for (int i = 1; i <= 12; i++) { if (numberOfDaysInMonth(i) < _day) { _day -= numberOfDaysInMonth(i); month++; } else if (numberOfDaysInMonth(i) == _day) { month++; break; } else { month++; break; } } if (_day < 10 && month < 10) { gregorianDate = year + "0" + month + "0" + _day; } else if (_day < 10 && month >= 10) { gregorianDate = year + "" + month + "0" + _day; } else if (_day >= 10 && month < 10) { gregorianDate = year + "0" + month + "" + _day; } else { gregorianDate = year + "" + month + "" + _day; } return gregorianDate; } public String dayOfTheWeekFromGregorianDate(String inDate) { String day = inDate.charAt(6) + "" + inDate.charAt(7);//k - day String month = inDate.charAt(4) + "" + inDate.charAt(5);//month String year = inDate.charAt(2) + "" + inDate.charAt(3);//year int k = getValueOrNegativeOneForIntegers(day); int m = getValueOrNegativeOneForIntegers(month); int y = getValueOrNegativeOneForIntegers(year); int t[] = {0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4}; y -= (m < 3) ? 1 : 0; int w = ((y + y / 4 - y / 100 + y / 400 + t[m - 1] + k) % 7); return getDayOfTheWeek(w); } public String daysDiff(String date1, String date2) { date1 = gregorianDateToJulianDate(date1); date2 = gregorianDateToJulianDate(date2); String year1 = date1.charAt(0) + "" + date1.charAt(1) + "" + date1.charAt(2) + "" + date1.charAt(3); String day1 = date1.charAt(4) + "" + date1.charAt(5) + "" + date1.charAt(6); String year2 = date2.charAt(0) + "" + date2.charAt(1) + "" + date2.charAt(2) + "" + date2.charAt(3); String day2 = date2.charAt(4) + "" + date2.charAt(5) + "" + date2.charAt(6); int _year1 = getValueOrNegativeOneForIntegers(year1); int _day1 = getValueOrNegativeOneForIntegers(day1); int _year2 = getValueOrNegativeOneForIntegers(year2); int _day2 = getValueOrNegativeOneForIntegers(day2); int yearDifference = Math.abs(_year1 - _year2); int yearDifferenceInDays = (yearDifference / 4) + (365 * yearDifference); int dayDifferenceIs = yearDifferenceInDays + (Math.abs(_day1 - _day2)); if (getIsItALeapYear(_year1)) { dayDifferenceIs++; } if (getIsItALeapYear(_year2)) { dayDifferenceIs++; } return dayDifferenceIs + ""; } private boolean getIsItALeapYear(int year) { if (year % 4 == 0) { return true; } return false; } private String getDayOfTheWeek(int w) { switch (w) { case 0: return "Sunday"; case 1: return "Monday"; case 2: return "Tuesday"; case 3: return "Wednesday"; case 4: return "Thursday"; case 5: return "Friday"; case 6: return "Saturday"; } return null; } private int monthToDays(int month) { int days = 0; for (int i = 1; i <= month - 1; i++) { days += numberOfDaysInMonth(i); } return days; } private int numberOfDaysInMonth(int month) { switch (month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: return 31; case 2://February if (isItALeapYear) { return 29; } return 28; case 4: case 6: case 9: case 11: return 30; } return -1; } private void println(String text) { System.out.println(text); } private int getValueOrNegativeOneForIntegers(String input) { int result; try { result = Integer.valueOf(input); } catch (NumberFormatException exception) { result = -1; } return result; }}
Testing
import java.util.Scanner;public class Test { private static Scanner kb = new Scanner(System.in); public static void main(String[] args) { DateUtil test = new DateUtil(); int userChoice; do { System.out.println("[0] to quit \n" + "[1] To Check Your gregorian date\n" + "[2] To check your julian date\n" + "[3] To convert gregorian to Julian\n" + "[4] To convert Julian to Gregorian\n" + "[5] To find what day of the week your gregorian date occurred in\n" + "[6] To find the difference between two dates in DAYS\n" + "[7] To find the number of days worked in a normal work schedule && \n" + "number of days worked during a holiday"); userChoice = kb.nextInt(); switch (userChoice) { case 0: quit(); break; default: case 1: System.out.println("Enter Gregorian Date Ex yyyymmdd"); if (test.checkGregorianDate(kb.next())) { System.out.println("Your date is Valid good job"); } else { System.out.println("Invalid Gregorian Date"); } System.out.println("Process Complete..."); break; case 2: System.out.println("Enter Julian Date Ex yyyyddd"); if (test.checkJulianDate(kb.next())) { System.out.println("Your date is Valid good job"); } else { System.out.println("Invalid Julian Date"); } System.out.println("Process Complete..."); break; case 3: System.out.println("Enter Gregorian Date Ex yyyymmdd"); String gregorianDate = kb.next(); if (test.checkGregorianDate(gregorianDate)) { System.out.println("Your Julian date is: " + test.gregorianDateToJulianDate(gregorianDate)); System.out.println("Process Complete..."); } else { System.out.println("Sorry can't process this since it's incorrect"); System.out.println("Process Complete..."); } break; case 4: System.out.println("Enter Julian Date Ex yyyyddd"); String julianDate = kb.next(); if (test.checkJulianDate(julianDate)) { System.out.println("Your Gregorian date is: " + test.julianDateToGregorianDate(julianDate)); System.out.println("Process Complete..."); } else { System.out.println("Sorry can't process this since it's incorrect"); } break; case 5: System.out.println("Enter Gregorian Date Ex yyyymmdd"); String gregorianDate2 = kb.next(); if (test.checkGregorianDate(gregorianDate2)) { System.out.println("Your date is Valid, I will continue"); System.out.println("Your date tells me that that day of the week is: " + test.dayOfTheWeekFromGregorianDate(gregorianDate2)); } else { System.out.println("Invalid Gregorian Date"); } System.out.println("Process Complete..."); break; case 6: String startDate, endDate; do { System.out.println("Enter start date(Gregorian): "); startDate = kb.next(); } while (!test.checkGregorianDate(startDate)); do { System.out.println("Enter end date(Gregorian): "); endDate = kb.next(); } while (!test.checkGregorianDate(endDate)); System.out.println("The difference between the two dates is: " + test.daysDiff(startDate, endDate)); break; case 7: String startDateWork, endDateWork, startDateHoliday, endDateHoliday; do { System.out.println("Enter start work date(Gregorian): "); startDateWork = kb.next(); } while (!test.checkGregorianDate(startDateWork)); do { System.out.println("Enter end work date(Gregorian): "); endDateWork = kb.next(); } while (!test.checkGregorianDate(endDateWork)); do { System.out.println("Enter start holiday date(Gregorian): "); startDateHoliday = kb.next(); } while (!test.checkGregorianDate(startDateHoliday)); do { System.out.println("Enter end holiday date(Gregorian): "); endDateHoliday = kb.next(); } while (!test.checkGregorianDate(endDateHoliday)); test.daysTypeCount(startDateWork, endDateWork, startDateHoliday, endDateHoliday); System.out.println("The days you worked on the holidays are: " + test.getHolidaysWorked()); System.out.println("The days you worked on your normal work days are: " + test.getWorkDaysWorked()); break; } } while (userChoice != 0); } private static void quit() { System.out.print("App is shutting down...."); }}