Question

Write a class called Date that represents a date consisting of a year, month, and day. A Date object should have the following methods: public Date(int year, int month, int day) Constructs a new Date object to represent the given date. public void addDays(int days) Moves this Date object forward in time by the given number of days. public void addWeeks(int weeks) Moves this Date object forward in time by the given number of seven-day weeks. public int daysTo( Date other) Returns the number of days that this Date must be adjusted to make it equal to the given other Date. public int getDay() Returns the day value of this date; for example, for the date 2006/07/22, returns 22. public int getMonth() Returns the month value of this date; for example, for the date 2006/07/22, returns 7. public int getYear() Returns the year value of this date; for example, for the date 2006/07/22, returns 2006. public boolean isLeapYear() Returns true if the year of this date is a leap year. A leap year occurs every four years, except for multiples of 100 that are not multiples of 400. For example, 1956, 1844, 1600, and 2000 are leap years, but 1983, 2002, 1700, and 1900 are not public String toString() Returns a String representation of this date in year/month/day order, such as "2006/07/22".

Answer 1

//Date.java

public class Date {

      

       private int day;

       private int month;

       private int year;

      

       // constructor

       public Date(int year, int month, int day)

       {

             this.year = year;

             this.month = month;

             this.day = day;

       }

      

       // method to add days in the current Date

       public void addDays(int days)

       {

             day += days;

             // loop that continues till we the valid date

             while(day > days_in_month(month))

             {     

                    day -= days_in_month(month);

                    month++;

                    if(month > 12)

                    {

                           year++;

                           month=1;

                    }

             }

       }

      

       // helper method to get the number of days in a given month

       private int days_in_month(int month)

       {

             if(month == 1 || month == 3 || month == 5 || month== 7 || month == 8 || month == 10 || month == 12)

                    return 31;

             else if(month == 4 || month == 6 || month == 9 || month == 11)

                    return 30;

             else {

                    if(isLeapYear()) // if month = 2, and it is a leap year

                           return 29;

                    else

                           return 28;

             }

       }

      

       // method to add weeks to the Date

       public void addWeeks(int weeks)

       {

             addDays(weeks*7);

       }

      

       // method to return the number of days that this Date must be adjusted to make it equal to the given Date

       public int daysTo(Date other)

       {

             int days = 0;

             // loop to add the number of days between this year and other’s year

             for(int i=year+1;i<other.getYear();i++)

             {

                    if((i%400 == 0) || ((i%4 == 0) && (i%100 != 0)))

                           days += 366;

                    else

                           days += 365;

             }

            

             // if both years are same

             if(year == other.getYear())

             {

                    // loop to add the number of days between the months

                    for(int i=month+1;i<other.getMonth();i++)

                           days += days_in_month(i);

      

                    days += days_in_month(month) - day; // add the days left in this month

                    days += other.getDay(); // add the days passed in other month

             }else

             {

                    // loop to add the number of days left in this year

                    for(int i=month+1;i<=12;i++)

                           days += days_in_month(i);

                   

                    days += days_in_month(month) - day; // add the days left in this year

                    // add the number of days passed in other year

                    for(int i=1;i<other.month;i++)

                           days += other.days_in_month(i);

                    days += other.getDay(); // add the number of days passed in other month

             }

            

             return days;

       }

      

       // method to return the day

       public int getDay()

       {

             return day;

       }

      

       // method to return the month

       public int getMonth()

       {

             return month;

       }

      

       // method to return the year

       public int getYear()

       {

             return year;

       }

      

       // method to check if the year is a leap year

       public boolean isLeapYear()

       {

             return((year%400 == 0) || ((year%4 == 0) && (year%100 != 0)));

       }

      

       public String toString()

       {

             return(year+"/"+String.format("%02d", month)+"/"+String.format("%02d", day));

       }

}

//end of Date.java