How can I know all the tuesdays of a given month?

Question

For instance in Sept I would need:

1,8,15,22 and 29

Thanks

Answer 1

Look up the Doomsday Rule - you should be able to apply that algorithm to your problem.

Answer 2

The simplest (naive) solution I can see is:

Get a Calendar (Calendar.getInstance())

Set the year, month, date etc (zero out other fields).

Then iterate adding one to the date (stop if you're not in the correct month - calendar.get(Calendar.MONTH))

while iterating, if calendar.get(Calendar.DAY_OF_WEEK) == Calendar.TUESDAY then increment the Tuesday counter.

Answer 3

As per daveb answer I've got:

import java.util.Calendar;
import static  java.util.Calendar.*;

public class DiasDelMes {

    public static void main( String [] args ) {

        Calendar calendar = getInstance();

        calendar.set( DAY_OF_MONTH, 1  );

        int month = calendar.get( MONTH );

        while( calendar.get( MONTH ) == month ) { 

            if( calendar.get( DAY_OF_WEEK ) == TUESDAY ) {
                 System.out.println( calendar.get( DAY_OF_MONTH ) ) ;
            }

            calendar.add( DAY_OF_MONTH , 1 ); 
       }
    }
}