BlueJ Program To Find The Total Number Of Days Between Two Dates

In this BlueJ program, two dates in dd/mm/yyyy format are to be entered and the total number of days between the dates will be calculated and displayed.

Codes of the program

import java.io.*;

class Array1

{

int arr[]={ 31,28,31,30,31,30,31,31,30,31,30,31};

int d1=-1,m1=-1,y1,d2=-1,m2=-1,y2,days=0,mon1,mon2;

int i,j;

String str,start,end;

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

public void take() throws IOException

{

 System.out.print("Enter the start date in dd/mm/yyyy format:");

 start=br.readLine();

  System.out.print("Enter the end date in dd/mm/yyyy format:");

 end=br.readLine();

while(true)

{

 i=start.indexOf("/");

 if(i< 0)

 break;

 str=start.substring(0,i);

 if(d1==-1)

 d1=Integer.parseInt(str);

 else if(m1==-1)

 m1=Integer.parseInt(str);

 start=start.substring(i+1);

}

y1=Integer.parseInt(start);

while(true)

{

 i=end.indexOf("/");

 if(i< 0)

 break;

 str=end.substring(0,i);

 if(d2==-1)

 d2=Integer.parseInt(str);

 else if(m2==-1)

 m2=Integer.parseInt(str);

 end=end.substring(i+1);

}

y2=Integer.parseInt(end);

days=arr[m1-1]-d1;

days=days+d2;

m2=m2-1;

mon2=m2;

for(i=y1;i< =y2;i++)

{

 if(i!=y1)

 m1=0;

 if(i!=y2)

m2=12;

else if(i==y2)

m2=mon2;

for(j=m1;j< m2;j++)

{

days=days+arr[j];

}

if(leap(i) && m2>2)

days++;

}

System.out.println("Total number of days="+days);

}

 private boolean leap(int yyyy)

 {

      if(yyyy%100==0 && yyyy%400==0)

      return true;

      else if(yyyy%100!=0 && yyyy%4==0)

      return true;

      else

      return false;

    }

  public static void main(String args[]) throws Exception

{

 Array1 ob=new Array1();

 ob.take();

}

}

Technical analysis of this program

Two dates are taken and the day,month and year of the dates are extracted and stored in variables like ‘d1’,’m1’,’y1’, ‘d2’,’m2’,’y2’. The number of days of each month are stored in a array. The counter variable, here ‘days’ in the program is initialized with the remaining number of days of the first month of the starting date plus number of days of the last month of the ending date. The days inbetween the starting and ending dates are stored in the counter variable using a loop. For leap year checking a function is defined in this program.

Related Post: BlueJ Programs on Numeric Array

Sample input and output of the program

 Enter the start date in dd/mm/yyyy format:1/1/2010

Enter the end date in dd/mm/yyyy format:1/4/2011

Total number of days=455

Enter the start date in dd/mm/yyyy format:1/1/2010

Enter the end date in dd/mm/yyyy format:1/1/2012

Total number of days=730