chore: create clean task

src/nextday/Date.java

-package nextday;
-
-public class Date {
-	private int day;
-	private Month month;
-	private int year;
-	
-	public Date(int day, Month month, int year) throws DateException {	
-		validateDate(day, month, year);
-		this.day = day;
-		this.month = month;
-		this.year = year;	
-	}
-	
-	public Date getNextDay() {
-		try {
-			Date newDate = new Date(day, month, year);
-
-			if (day == 29 & month == Month.FEBRUARY) {
-				newDate.setDay(1);
-				newDate.setMonth(Month.MARCH);
-				return newDate;
-			}
-
-			if (day == 28 & month == Month.FEBRUARY & isLeapYear(year)) {
-				newDate.setDay(29);
-				return newDate;
-			}
-
-			if (day == 28 & month == Month.FEBRUARY & !isLeapYear(year)) {
-				newDate.setDay(1);
-				newDate.setMonth(Month.MARCH);
-				return newDate;
-			}
-
-			if (!isLongMonth(month) && day == 30) {
-				newDate.setDay(1);
-				newDate.setMonth(month.getNextMonth());
-				return newDate;
-			}
-
-			if (day == 31) {
-				newDate.setDay(1);
-				if (month == Month.DECEMBER) {
-					newDate.setMonth(Month.JANUARY);
-					newDate.setYear(year + 1);
-				} else {
-					newDate.setMonth(month.getNextMonth());
-				}
-				return newDate;
-			}
-			newDate.setDay(day + 1);
-
-			return newDate;
-
-		} catch (DateException e) {
-			throw new RuntimeException("If this is thrown that either means your algorithm or your validation is buggy.");
-		}
-	}
-	
-	private boolean isLeapYear(int year){
-		if(year%400==0){
-			return true;
-		}
-		if(year%4==0 & year%100!=0){
-			return true;
-		}
-		return false;
-	}
-	
-	private boolean isLongMonth(Month month) {
-		switch (month) {
-		case FEBRUARY:
-		case APRIL:
-		case JUNE:
-		case SEPTEMBER:
-		case NOVEMBER:
-			return false;
-		default:
-			return true;
-		}
-	}
-
-	private void validateDate(int day, Month month, int year) throws DateException {
-		if(day > 31 || day < 1){
-			throw new DateException("Invalid day.");
-		}
-
-		if(year < 0){
-			throw new DateException("Invalid year.");
-		}
-		
-		if(!isLongMonth(month) & day > 30){
-			throw new DateException("Invalid day in month.");
-		}
-		
-		if(!isLeapYear(year) & day > 28 & month == Month.FEBRUARY){
-			throw new DateException("Invalid day in month.");
-		}
-		
-		if(isLeapYear(year) & day > 29 & month == Month.FEBRUARY){
-			throw new DateException("Invalid day in month.");
-		}	
-	}
-
-    private void setMonth(Month month) {
-        this.month = month;
-    }
-
-    private void setDay(int day) {
-        this.day = day;
-    }
-
-    private void setYear(int year) {
-        this.year = year;
-    }
-
-    @Override
-    public String toString() {
-        return "" + this.day + "." + (this.month.ordinal() + 1) + "." +  this.year;
-    }
-}

src/nextday/DateException.java

-package nextday;
-
-public class DateException extends Exception {
-	public DateException() {
-		super("The specified date is invalid!");
-	}
-
-	public DateException(String errorDescription) {
-		super(errorDescription);
-	}
-}

src/nextday/Month.java

-package nextday;
-
-public enum Month {
-	JANUARY, FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER, OCTOBER,
-	NOVEMBER, DECEMBER;
-
-	public Month getNextMonth() {
-		return values()[(ordinal() + 1) % values().length];
-	}
-}

src/nextday/NextDay.java

-package nextday;
-
-public class NextDay {
-	public static void main(String[] args)  throws DateException {
-		Date date = new Date(31, Month.DECEMBER, 2024);
-		System.out.println("Old date: " + date);
-		Date newDate = date.getNextDay();
-		System.out.println("New date: " + newDate);
-	}
-}