How to calculate next date in Java

[Former Member]

Hi Experts,

I am using Web Dynpro program. The BAPI returns first day of week (i.e. Monday). I have to calculate dates of Tuesdays, Wednesdays, Thursdays, Fridays, Saturdays and Sundays based on BAPI output. For example, suppose BAPI has recturned Monday Feb 25, 2007. Based on this, I have to calculate what will be the dates Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday. How can we calculate this quickly in Java?

Regards,

Brian

[Former Member · Accepted solution]

Here is a very comprehensive article about date and date manipulation:

<a href="http://www.onjava.com/pub/a/onjava/2003/06/05/java_calendar.html">See article (O'Reilly)</a>

Otherwise lookup the add method of the java.util.Calendar class....

Have you tried:

Calendar mycal = new Calendar();

mycal.setDate(sapdate);

mycal.add(Calendar.DATE, 1);

Enjoy and attribute points

[Former Member]

Hi,

U can use the following code to serve your purpose :

public class DateUtility {	/* Add Day/Month/Year to a Dateadd() is used to add  values to a Calendar object. You specify which Calendar field is to be affected by the operation (Calendar.YEAR, Calendar.MONTH, Calendar.DATE). */	public static void addToDate(){		System.out.println("In the ADD Operation");	//	String DATE_FORMAT = "yyyy-MM-dd";		String DATE_FORMAT = "dd-MM-yyyy";		//Refer Java DOCS for formats		java.text.SimpleDateFormat sdf =  new java.text.SimpleDateFormat(DATE_FORMAT);		Calendar c1 = Calendar.getInstance();		Date d1 = new Date();		System.out.println("Todays date in Calendar Format : "+c1);		System.out.println("c1.getTime() : "+c1.getTime());		System.out.println("c1.get(Calendar.YEAR): " + c1.get(Calendar.YEAR));		System.out.println("Todays date in Date Format : "+d1);		c1.set(1999,0 ,20); 		//(year,month,date)		System.out.println("c1.set(1999,0 ,20) : "+c1.getTime());		c1.add(Calendar.DATE,40);		System.out.println("Date + 20 days is : " + sdf.format(c1.getTime()));		System.out.println();		System.out.println();	}

public static void main(String args[]){	
	addToDate();
}

If it is helpful please reward with points.

Thanks

ritu

[former_member193726]

Hi Brian,

Here is the piece of code you are looking for.

<b>Assumption:</b>

The return type of the BAPI is a String. Example: <b>"Monday May 31, 2007"</b>

String day = "Monday May 31, 2007";

String year = day.substring(day.lastIndexOf(" ")+1, day.length());

String month = day.substring(day.indexOf(" ")1, day.indexOf(" ")4);

String date = day.substring(day.indexOf(" ")5, day.indexOf(" ")7);

Calendar cal = Calendar.getInstance();

int current_month = 0;

if(month.equals("Jan")){

current_month = 0;

}else if(month.equals("Feb")){

current_month = 1;

}else if(month.equals("Mar")){

current_month = 2;

}else if(month.equals("Apr")){

current_month = 3;

}else if(month.equals("May")){

current_month = 4;

}else if(month.equals("Jun")){

current_month = 5;

}else if(month.equals("Jul")){

current_month = 6;

}else if(month.equals("Aug")){

current_month = 7;

}else if(month.equals("Sep")){

current_month = 8;

}else if(month.equals("Oct")){

current_month = 9;

}else if(month.equals("Nov")){

current_month = 10;

}else if(month.equals("Dec")){

current_month = 11;

}

cal.set(Integer.parseInt(year), current_month, Integer.parseInt(date));

cal.add(Calendar.DATE, 1); //Tuesday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

cal.add(Calendar.DATE, 1); //Wednesday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

cal.add(Calendar.DATE, 1); //Thrusday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

cal.add(Calendar.DATE, 1); //Friday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

cal.add(Calendar.DATE, 1); //Saturday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

cal.add(Calendar.DATE, 1); //Sunday

System.out.println(cal.get(Calendar.MONTH));

System.out.println(cal.get(Calendar.DATE));

System.out.println(cal.get(Calendar.YEAR));

You need to append the output according to your convenience.

Hope this helps.

Regards,

Rekha Malavathu