use this
import java.text.SimpleDateFormat;
import java.util.Date;
public class HelloWorld {
public static void main(String[] args) throws Exception {
SimpleDateFormat formater=new SimpleDateFormat("yyyy-MM-dd");
long d1=formater.parse("2015-08-01").getTime();
long d2=formater.parse("2015-08-19").getTime();
int days = (int)Math.abs((d1-d2)/(1000*60*60*24)); // suppose 9 days
int number_of_weeks = (int)Math.ceil(days/7);
System.out.println(number_of_weeks); // use result.addValue() here
}
}
gives the week number as 2 if it has 14 to 20 days
if you want the celing value just give days/7.0 it will give the rounded up value