Question

General Requirements:

• You should create your programs with good programming style and form using proper blank spaces, indentation and braces to make your code easy to read and understand;

• You should create identifiers with sensible names;

• You should make comments to describe your code segments where they are necessary for readers to understand what your code intends to achieve.

• Logical structures and statements are properly used for specific purposes.

Objectives
This assignment requires you to write a program in Java that calculates the day of week and the week of month for a given date, as well as to print the calendar of the month where the given date exists. Please note, you are not allowed to use any date based classes predefined in Java JDK.
Background




For a given date, we can use the Gregorian calendar to find the corresponding the day of the week, and the week of the month. For example, May 25 2019 is a Saturday and locates in the fourth week of May 2019. In general, we can use the following formula (Zeller’s congruence) to calculate the day of a week for any given date after October 15 1582.



where
• h is the day of the week (0 = Saturday, 1 = Sunday, 2 = Monday, 3=Tuesday, 4=Wednesday, 5=Thursday, 6 = Friday)

• q is the day of the month

• m is the month (3 = March, 4 = April, 5 = May, 6=June, 7=July, 8=August, 9=September, 10=October, 11=November, 12=December, 13=January, 14 = February)

• K is the year of the century (year mod 100).

• J is the zero-based century (year/100). For example, the zero-based centuries for 1995 and 2000 are 19 and 20 respectively.
For example, For 1 January 2000, the date would be treated as the 13th month of 1999, so the values would be: q=1, m=13, K=99, J=19, so the formula is
h = (1+[13*(13+1)/5]+99+[99/4]+[19/4]+5*19) mod 7 = (1+[182/5]+99+[99/4]+[19/4]+95) mod 7 = (1+[36.4]+99+[24.75]+[4.75]+95) mod 7 = (1+36+99+24+4+95) mod 7 = 0 = Saturday

However, for 1 March 2000, the date is treated as the 3rd month of 2000, so the values become q=1, m=3, K=00, J=20, so the formula is

h = (1+[13*(3+1)/5]+00+[00/4]+[20/4]+5*20] mod 7 = (1+[10.4]+0+0+5+100) mod 7 = (1+10+5+100) mod 7 = 4 = Wednesday






Tasks You will create one program called MyCalendar.java. You should first implement the MyCalendar and MyDate classes from the following UML class diagrams. You can add extra attributes and methods, but the attributes and methods shown in the UML diagrams can’t be modified.

  

MyCalendar - myDate: MyDate - day: Day + Main(String[] args) + MyCalendar(MyDate myDate) + dayOfWeek(): Day + weekOfMonth(): int + printCalendar(): void
• Day is an enumeration data type which contains the days of the week, i.e., Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, and Sunday. • MyCalendar(MyDate myDate)is the construction method of the class MyCalendar. • dayOfWeek() method will return the day of the week for myDate. • weekOfMonth() method will return the week of the month for myDate. • printCalendar() method will print the calendar of the month for myDate. • Main(String[] args) method will read a given date from the command line, the format of the given date is dd/mm/yyyy. You can assume the date input format is always correct, but the input date may be invalid. For example, 31/02/2017 is not a valid date. If the input date is not a valid date, the program will ask user to input another valid date through keyboard. This process will be repeated until a valid date is input by the user. The valid input date will be used to create the object (myDate) of class MyDate, then the object (myCalendar) of class MyCalendar. The dayOfWeek() method, weekOfMonth() method, and printCalendar() method of myCalendar object will be called to display the day of the week, the week of the month, and the calendar of the month for the input date by the user.


MyDate
- day: int - month: int - year: int + MyDate(int day, int month, int year) + getDay(): int + getMonth(): int + getYear(): int + isDateValid(): boolean
• MyDate(int day, int month, int year) is the constructor of the class MyDate. • getDay() method returns the day of myDate object. • getMonth() method returns the month of myDate object. • getYear() method returns the year of myDate object. • isDateValid() method returns a Boolean value, i.e., a true when the myDate object is valid, and a false otherwise (notes: January, March, May, July, August, October, December has 31 days. April, June, September, November has 30 days. February has 29 days in a leap year, and 28 days in a common year.).

  
Your program must have the exact same output as the following example. Example of the program output:
java MyCalendar 29/02/2019 29/02/2019 in not a valid date, please re-input a valid date: 25/05/2019 25/05/2019 is a Saturday and located in the fourth week of May 2019 The calendar of May 2019 is:
SUN MON TUE WED THU FRI SAT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
(Note: Each column indicates a day and the column width are fixed to 3 characters. The distance between two adjacent columns is fixed to three characters as well.)

Answer 1

//MyDate.java

public class MyDate
{
int day,month,year;

boolean isvaliDate=true;

public MyDate(int day,int month,int year)
{
   this.day=day;
   this.month=month;
   this.year=year;

if(month>12)   //day and month validation

   {

     isvaliDate=false;

   }

else if(month==1 || month==3 || month==5 || month==7 || month==9 || month==12)

{

    if(day<=31)

   {

     isvaliDate=true;

   }

else if(day>=31)

   {

     isvaliDate=false;

   }

}

else if(month==2 || month==4 || month==6 || month==8 || month=10 || month==12)

{

if(day<=30)

   {

     isvaliDate=true;

   }

else if(day>=30)

   {

     isvaliDate=false;

   }

}

else if(month==2) //Feb month and leap year validation

{

   if(year%4==0)

{

    if(day<=29)

   {

     isvaliDate=true;

   }

else if(day>=29)

   {

     isvaliDate=false;

   }

}

else if(year%4!==0)

{

    if(day<=28)

   {

     isvaliDate=true;

   }

else if(day>=28)

   {

     isvaliDate=false;

   }

}

}

}

boolean isvalidDate()

{

if(isvalidDate)

{

System.out.println("is a Valid Date");

return true;

}

if( ! isvalidDate)

{

System.out.println("is not a Valid Date,please re-input Date");

return false;

}

return isvalidDate;

}

public int getDay()
{
   return day;
}
public int getMonth()
{
   return month;
}
public int getYear()
{
   return year;
}
public static void main(String[] args)
{
   MyDate d=new MyDate(29, 02, 2019);
   System.out.println("Date"+d.getDay()+"/"+d.getMonth()+"/"+d.getYear());
   d.isvalidDate();
  
   MyDate d1=new MyDate(25, 02, 2019);
   System.out.println("Date"+d1.getDay()+"/"+d1.getMonth()+"/"+d1.getYear());
   d1.isvalidDate();
}
              
}