Question

Java Programming:

Hi, I need help Modifying my code that will throw an IllegalArgumentException.

for the following data entry error conditions:

• A number less than 1 or greater than 12 has been entered for the month
• A negative integer has been entered for the year

utilizes a try and catch clause to display an appropriate message when either of these data entry errors exceptions occur. Thank you let me know if you need more info

import java.util.*;

//Class definition
public class MonthDays
{
private int month;
private int year;
  
//Constructor
public MonthDays(int month, int year)
{
this.month = month;
this.year = year;
}
  
//Method that returns number of days in a month
public int getNumberOfDays()
{
//Variable to hold status of leap year
boolean isLeapYear;
  
//Checking for leap year
//Checking Divisible by 100
if (year % 100 == 0)
{
//Checking Divisible by 400
if(year % 400 == 0)
{
isLeapYear = true;
}
else
{
isLeapYear = false;
}
}
else
{
//Checking Divisible by 4
if(year % 4 == 0)
{
isLeapYear = true;
}
else
{
isLeapYear = false;
}
}
  
//Fetching number of months
switch(month)
{
//For month 2
case 2:
//If leap year, days are 29
if(isLeapYear)
return 29;
//If not a leap year, days are 28
else
return 28;
  
//For the following months days are 31
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12: return 31;
  
//For the following months days are 30
case 4:
case 6:
case 9:
case 11: return 30;
}
  
return -1;
}
}

import java.util.*;

//Driver class
public class MonthDaysDriver
{
//Main method
public static void main(String args[])
{
int month, year;
  
//Scanner class object
Scanner sc = new Scanner(System.in);
  
//Reading month
System.out.print("\n\n Enter a month (1-12): ");
month = sc.nextInt();
  
//Reading year
System.out.print("\n\n Enter a year: ");
year = sc.nextInt();
  
//Creating object
MonthDays obj = new MonthDays(month, year);
  
//Printing number of days
System.out.println("\n " + obj.getNumberOfDays() + " days \n");
}
}

Answer 1

import java.util.*;

//Class definition

public class MonthDays {

private int month;

private int year;

// Constructor

public MonthDays(int month, int year) {

if (month < 0 || month > 12)

throw new IllegalArgumentException("Month should be in the range from (1-12)");

if (year < 0)

throw new IllegalArgumentException("Number cannot be negative");

this.month = month;

this.year = year;

}

// Method that returns number of days in a month

public int getNumberOfDays() {

// Variable to hold status of leap year

boolean isLeapYear;

// Checking for leap year

// Checking Divisible by 100

if (year % 100 == 0) {

// Checking Divisible by 400

if (year % 400 == 0) {

isLeapYear = true;

} else {

isLeapYear = false;

}

} else {

// Checking Divisible by 4

if (year % 4 == 0) {

isLeapYear = true;

} else {

isLeapYear = false;

}

}

// Fetching number of months

switch (month) {

// For month 2

case 2:

// If leap year, days are 29

if (isLeapYear)

return 29;

// If not a leap year, days are 28

else

return 28;

// For the following months days are 31

case 1:

case 3:

case 5:

case 7:

case 8:

case 10:

case 12:

return 31;

// For the following months days are 30

case 4:

case 6:

case 9:

case 11:

return 30;

}

return -1;

}

}

==========================================================

import java.util.*;

// Driver class

public class MonthDaysDriver {

// Main method

public static void main(String args[]) {

try {

int month, year;

// Scanner class object

Scanner sc = new Scanner(System.in);

// Reading month

System.out.print("\n\n Enter a month (1-12): ");

month = sc.nextInt();

// Reading year

System.out.print("\n\n Enter a year: ");

year = sc.nextInt();

// Creating object

MonthDays obj = new MonthDays(month, year);

// Printing number of days

System.out.println("\n " + obj.getNumberOfDays() + " days \n");

} catch (IllegalArgumentException e) {

System.err.println(e.getMessage());

}

}

}

====================================================================================

SEE OUTPUT

Thanks, PLEASE COMMENT if there is any concern.