In this section we are displaying the days of a specific month and the calendar format of the days for this month. We are also checking whether the year is leap or not.
Calendar
In this section we are displaying the days of a
specific month and the calendar format of the days for this month. We are
also checking whether the year is leap or not.
Description of program:
In the given example first we are taking a string array
monthcalendar that contains the name of the months of an year. After that we
are creating an integer type array that contains number of days in the months in
their respective order. Now we create a method displayMonth(). In this method we
are leaving the number of days blank at the start of the month, throwing an
illegalArgumentException object showing a message if the month value does not
lie in between 0 and 11. Now we are creating an object cldr of the
Gregoriancalendar class by passing the values of month and year and then printing
the days of the week on the console. Now we are getting the number of days to be
left blank at the start of a month by using the get() method of the
Gregoriancalendar class and also checking whether the year is leap or not and
printing the days of that month on the console.
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import java.util.*;
import java.text.*;
public class MonthCalender {
public final static String[] monthcalender = {
"January", "February", "March", "April", "May", "June", "July",
"August", "September", "October", "November", "December"};
public final static int daysinmonths[] = {31, 28, 31, 30, 31,
30, 31, 31, 30, 31, 30, 31 };
private void displayMonth(int month, int year) {
// The number of days to leave blank at
// the start of this month.
int blankdays = 0;
System.out.println(" " + monthcalender[month] + " " + year);
if (month < 0 || month > 11) {
throw new IllegalArgumentException(
"Month " + month + " is not valid and must lie in
between 0 and 11");
}
GregorianCalendar cldr = new GregorianCalendar(year,
month, 1);
System.out.println("Sunday Monday Tuesday Wednesday
Thirsday Friday Saturday");
// Compute how much to leave before before the first
day of the month.
// getDay() returns 0 for Sunday.
blankdays = cldr.get(Calendar.DAY_OF_WEEK)-1;
int daysInMonth = daysinmonths[month];
if (cldr.isLeapYear(cldr.get(Calendar.YEAR))
&& month == 1) {
++daysInMonth;
}
// Blank out the labels before 1st day of the month
for (int i = 0; i < blankdays; i++) {
System.out.print(" ");
}
for (int i = 1; i <= daysInMonth; i++) {
// This "if" statement is simpler than
messing with NumberFormat
if (i<=9) {
System.out.print(" ");
}
System.out.print(i);
if ((blankdays + i) % 7 == 0) { // Wrap if EOL
System.out.println();
}
else {
System.out.print(" ");
}
}
}
/**
* Sole entry point to the class and application.
* @param args Array of String arguments.
*/
public static void main(String[] args) {
int mon, yr;
MonthCalender moncldr = new MonthCalender();
if (args.length == 2) {
moncldr.displayMonth(Integer.parseInt(args[0])-1,
Integer.parseInt(args[1]));
}
else {
Calendar todaycldr = Calendar.getInstance();
moncldr.displayMonth(todaycldr.get(Calendar.MONTH)
, todaycldr.get(Calendar.YEAR));
}
}
}
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Here is the output:
C:\Examples>java MonthCalender
December 2007
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
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 |
Download of this program.
