Question

in java please

Purpose: To practice designing a class that can be used in many applications. To write and implement a thorough test plan. You are NOT to use any of the Java API date classes (Gregorian calendar, Date…) except for the constructor method to set the date fields to the current data.

Write a class to hold data and perform operations on dates. Ie: January 2, 2019   or 3/15/2018

You must include a toString( ), an equals( ) and a compareTo( ) method.

Methods required in addition to the several constructor methods (including the copy constructor),the
toString( ), equals( ), compareTo( ), set( ) methods:

public Date add(int numDays)
public Date subtract(int numDays)

public int daysBetween(Date anotherDate)

public String getDate(char format)//allow representations in various fomats ie: January 5, 2019 or 1/5/2019

You will receive ten points extra credit if you consider leap years in your calculations.

Once you unit test each method using the BlueJ debugging tools, write a driver class with main( ) that tests each of the methods thoroughly. This is part of the thought processes/skills of programming that is essential. Test all possible scenarios and print statements to the screen to show what you are testing and the results of the test.

You will not get credit for any method that is not tested and test results printed from main( ).

Come up with your own ideas of what a user would want to do with a Date object. Test and document each.

Answer 1

ANSWER:

public class Date
{
private int day;
private int month;
private int year;

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

public string toString()
{
return (this.day + "-" + this.month + "-" + this.year);
}

public bool equals(Date date)
{
return (this.day == date.day &&
this.month == date.month &&
this.year == date.year);
}

public bool equals(Date date, Date date1)
{
return (date.day == date1.day &&
date.month == date1.month &&
date.year == date1.year);
}

public Date add(int numDays)
{
var tempDays = this.GetDaysInCurrentMonth();
while (numDays > tempDays)
{
this.month = this.GetNextMonth();
if (this.month == 1)//Again got Jan, year shouls be incremeneted
{
this.year = this.year + 1;
}

tempDays = this.GetDaysInCurrentMonth();
numDays = numDays - tempDays;
}

this.day = numDays;
  
return this;
}

public int daysBetween(Date anotherDate)
{
if(this.year > anotherDate.year)
{
return (this.year - anotherDate.year) * 365;//in year 365 days are there
}
  
else if(this.day > anotherDate.day)
{
return this.day - anotherDate.day;
}

return this.day - anotherDate.day;
}

public string getDate(char format)
{
if(format == 's')
{
return this.day + "//" + this.month + "//" + this.year;
}
else if(format == 'l')
{
return this.day + "of " + this.month + ", " + this.year;
}

return this.day + "//" + this.month + "//" + this.year;
}

public Date subtract(int numDays)
{
var tempDays = this.GetDaysInCurrentMonth();
while (numDays > tempDays)
{
this.month = this.GetPrevMonth();
if (this.month == 12)//Again got Jan, year shouls be incremeneted
{
this.year = this.year - 1;
}

tempDays = this.GetDaysInCurrentMonth();
numDays = numDays - tempDays;
}

this.day = this.GetDaysInCurrentMonth() - numDays;

return this;
}

private int GetDaysInCurrentMonth()
{
int noOfDaysInMonth = -1;
switch(this.month)
{
case 1://Jan
noOfDaysInMonth = 31;
break;

case 2://Feb
if(this.year % 400 == 0)//If leapyear
{
noOfDaysInMonth = 29;
}
else
{
noOfDaysInMonth = 28;
}
break;

case 3://March
noOfDaysInMonth = 31;
break;

case 4://April
noOfDaysInMonth = 30;
break;

case 5://May
noOfDaysInMonth = 30;
break;

case 6://Jun
noOfDaysInMonth = 30;
break;

case 7://Jul
noOfDaysInMonth = 31;
break;

case 8://Aug
noOfDaysInMonth = 31;
break;

case 9://Sept
noOfDaysInMonth = 30;
break;

case 10://Oct
noOfDaysInMonth = 31;
break;

case 11://Nov
noOfDaysInMonth = 30;
break;

case 12://Dec
noOfDaysInMonth = 31;
break;
}

return noOfDaysInMonth;
}

private int GetNextMonth()
{
int nextMonth = -1;
switch(this.month)
{
case 1:
nextMonth = 2;
break;

case 2:
nextMonth = 3;
break;

case 3:
nextMonth = 4;
break;

case 4:
nextMonth = 5;
break;

case 5:
nextMonth = 6;
break;

case 6:
nextMonth = 7;
break;

case 7:
nextMonth = 8;
break;

case 8:
nextMonth = 9;
break;

case 9:
nextMonth = 10;
break;

case 11:
nextMonth = 12;
break;

case 12:
nextMonth = 1;
break;

}

return nextMonth;
}

private int GetPrevMonth()
{
int nextMonth = -1;
switch (this.month)
{
case 1:
nextMonth = 12;
break;

case 2:
nextMonth = 1;
break;

case 3:
nextMonth = 2;
break;

case 4:
nextMonth = 3;
break;

case 5:
nextMonth = 4;
break;

case 6:
nextMonth = 5;
break;

case 7:
nextMonth = 6;
break;

case 8:
nextMonth = 7;
break;

case 9:
nextMonth = 8;
break;

case 11:
nextMonth = 10;
break;

case 12:
nextMonth = 11;
break;

}

return nextMonth;
}
}