Java program for generating the calendar of any desired year and month let us first go through an illustration before landing upon logic and procedural part.
Illustration:
Say the user wants to get the calendar of April 2011. Then, he is required to enter the year along with the month as integers and the output would return the desired month’s calendar for the respective year in a proper format.
Procedure:
Step 1: Take the year and the month as integer inputs from the user
Step 2: Create 2 arrays as follows, one for storing days and the other for storing the months, as per proper order.
String day[] = { "SUN","MON","TUE","WED","THU","FRI","SAT" } ; String month[] = { "JANUARY","FEBRUARY","MARCH","APRIL","MAY","JUNE","JULY","AUGUST","SEPTEMBER","OCTOBER","NOVEMBER","DECEMBER" } ;
Step 3: Initialize a counter variable and three variables, each for the day, month, and year as 1, and a separate array for storing the different combinations of days on which months can be found. Eg. 31,30,29
int ar[] = { 31,29,31,30,31,30,31,31,30,31,30,31 } ;
Step 4: Check the leap year condition and re-initialize values for the above array.
if(y%4==0&&y%100!=0||y%100==0) ar[1]=29; // if the year is a leap year then store 29 for the month of february else ar[1]=28; // else 28
Step 5: Increment year count as month count reaches 12 and increment month count as day count reaches a value greater than that present in the array for the respective index
Step 6: Print the result.
Implementation:
Example
// Java Program to Generate Desired Calendar // Without calendar.get() function or // Inputting the Year and the Month // Importing required classes import java.io.*;
import java.util.Scanner;
// Main class public class GFG {
// Main driver method
public static void main(String a[])
{
// Reading input by creating object of Scanner class
Scanner sc = new Scanner(System.in);
// Display message only
System.out.print( "Enter the year : " );
// Reading integer input value
int yy = sc.nextInt();
// Display message only
System.out.print( "Enter month : " );
// Reading integer input value
int mm = sc.nextInt();
int d = 1 ;
int m = 1 ;
int y = 1 ;
int dy = 1 ;
// Storing data and months as input
String day[] = { "SUN" , "MON" , "TUE" , "WED" ,
"THU" , "FRI" , "SAT" };
String month[]
= { "JANUARY" , "FEBRUARY" , "MARCH" ,
"APRIL" , "MAY" , "JUNE" ,
"JULY" , "AUGUST" , "SEPTEMBER" ,
"OCTOBER" , "NOVEMBER" , "DECEMBER" };
// Custom array as input
int ar[] = { 31 , 29 , 31 , 30 , 31 , 30 ,
31 , 31 , 30 , 31 , 30 , 31 };
// Till condition holds true
while ( true ) {
if (d == 1 && m == mm && y == yy) {
break ;
}
if (y % 4 == 0 && y % 100 != 0
|| y % 100 == 0 ) {
ar[ 1 ] = 29 ;
}
else {
ar[ 1 ] = 28 ;
}
dy++;
d++;
if (d > ar[m - 1 ]) {
m++;
d = 1 ;
}
if (m > 12 ) {
m = 1 ;
y++;
}
if (dy == 7 ) {
dy = 0 ;
}
}
int c = dy;
if (y % 4 == 0 && y % 100 != 0 || y % 400 == 0 ) {
ar[ 1 ] = 29 ;
}
else {
ar[ 1 ] = 28 ;
}
// Print the desired month of input year
System.out.println( "MONTH:" + month[mm - 1 ]);
for ( int k = 0 ; k < 7 ; k++) {
System.out.print( " " + day[k]);
}
System.out.println();
for ( int j = 1 ; j <= (ar[mm - 1 ] + dy); j++) {
if (j > 6 ) {
dy = dy % 6 ;
}
}
int spaces = dy;
if (spaces < 0 )
spaces = 6 ;
// Printing the calendar
for ( int i = 0 ; i < spaces; i++)
System.out.print( " " );
for ( int i = 1 ; i <= ar[mm - 1 ]; i++) {
System.out.printf( " %4d " , i);
if (((i + spaces) % 7 == 0 )
|| (i == ar[mm - 1 ]))
System.out.println();
}
}
} |
Output: