GoogleCalendarMaker.java

package org.dtph.model;


import java.io.PrintStream;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 *
 * @author christoforosl
 */
public class GoogleCalendarMaker {
	
	public static void main(String[] args) throws Exception {
		
		final GoogleCalendarMaker googleCalendarMaker = new GoogleCalendarMaker();
		Calendar c = Calendar.getInstance();
		c.set( 2019, 1, 10, 5 , 30 ,0 );
		googleCalendarMaker.neededItems = 200;
		googleCalendarMaker.startFrom = c.getTime();
		//googleCalendarMaker.direction = 1;
		googleCalendarMaker.make();
		googleCalendarMaker.print( System.err );

	}
	
	final SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
	private static final String EVENT_TEMPLATE = "BEGIN:VEVENT\nDTSTART:%s\nDTEND:%s\nSUMMARY:%s\nX-GOOGLE-CALENDAR-CONTENT-TITLE:%s\nX-GOOGLE-CALENDAR-CONTENT-TYPE:text/html\nEND:VEVENT\n\n";
	private final StringBuilder calendarCode = new StringBuilder("BEGIN:VCALENDAR\nVERSION:2.0\nX-WR-CALNAME:MARATHONTRAINING\nX-WR-TIMEZONE:Europe/London\nCALSCALE:GREGORIAN\n\n"); 
	//private int direction = 0 ;
	private int itemCounter = 0;
	private int neededItems = 100;
	private String itemType = "w";
	private Date startFrom;
	

	public void make() {
		final Calendar c = Calendar.getInstance();
		c.setTime( this.startFrom );
		int weeknum = 8;
		
		while(itemCounter < neededItems) {
			String title = "";
			if ( c.get(Calendar.DAY_OF_WEEK)  == Calendar.SUNDAY) {
				weeknum++;
				title =  "W"+weeknum+" 5 Miles Easy Run (8km)"; //itemCounter > 0 ?  "Athens Marathon " + itemCounter + " week(s) Left!!" : "Athens Marathon Date" ; 
				
			} else if ( c.get(Calendar.DAY_OF_WEEK)  == Calendar.MONDAY) {
				title =  "W"+weeknum+" Strength Training";	
				
			} else if ( c.get(Calendar.DAY_OF_WEEK)  == Calendar.FRIDAY) {
				title =  "W"+weeknum+" Strength Training";	
				
			} else if ( c.get(Calendar.DAY_OF_WEEK)  == Calendar.SATURDAY) {
				title =  "W"+weeknum+" Long Run"; //itemCounter > 0 ?  "Athens Marathon " + itemCounter + " week(s) Left!!" : "Athens Marathon Date" ; 
			} else {
				title =  "W"+weeknum+" Run"; //itemCounter > 0 ?  "Athens Marathon " + itemCounter + " week(s) Left!!" : "Athens Marathon Date" ; 
			}
			
			if (weeknum > 16) {
				break;
			} 
			
			final String summary=title; //itemCounter > 0 ? itemCounter + " weeks left until the Athens Marathon." : "Athens Marathon Date" ; 
			final String formattedEntry = String.format(EVENT_TEMPLATE, sdf.format(c.getTime())+"T033000", sdf.format(c.getTime())+"T043000", summary, title  );
			calendarCode.append(formattedEntry);
			
			//int numToAdd =  direction ==0 ?  1 : -1; 
			c.add(Calendar.DAY_OF_MONTH, 1);
			itemCounter++;
			
		}
		
		calendarCode.append("END:VCALENDAR");

	}
	
	private void print( PrintStream pstr ) {
		
		pstr.print( calendarCode );
		
	}
	
}