Using a non default Calendar in the Google API

All the examples in the Google Calendar API documentation involve using a default calendar. But i was looking at a project where i would have a shared calendar among users and this calendar would not be the default one. The simple code below demonstrates how to do this in Java. There are three parameter you will need to inject into this class (in my case via Spring) -- the username, password, and calendarname. Using these three you have what you need to work with the non default calendar.

   1: public class CalendarUtil {

   2:   private final static Logger logger = Logger.getLogger(CalendarUtil.class.getName());

   3:   private String username;

   4:   private String password;

   5:   String calendarName;

   6:   private URL calendarUrl;

   7:  

   8:   private CalendarService service;

   9:  

  10:   // The base URL for a user's calendar metafeed (needs a username appended).

  11:   private static final String METAFEED_URL_BASE =

  12:           "http://www.google.com/calendar/feeds/";

  13:  

  14:   private static final String CALENDAR_URL_SUFFIX = "/private/full";

  15:  

  16:   public void init() {

  17:     service = new CalendarService("DR-Appt-App-1");

  18:     try {

  19:       service.setUserCredentials(username, password);

  20:     } catch (AuthenticationException e) {

  21:       throw new RuntimeException("Could not authenticate to Google Calendar with username: " + username, e);

  22:     }

  23:     String calendarId = null;

  24:     try {

  25:       calendarId = getCalendarId();

  26:     } catch (IOException e) {

  27:       throw new RuntimeException("Error caught trying to connect to calendar: ", e);

  28:     } catch (ServiceException e) {

  29:       throw new RuntimeException("Error caught trying to connect to calendar: ", e);

  30:     }

  31:     try {

  32:       calendarUrl = new URL(METAFEED_URL_BASE + calendarId + CALENDAR_URL_SUFFIX);

  33:     } catch (MalformedURLException e) {

  34:       throw new RuntimeException("Bad URL: " + calendarUrl.toString(), e);

  35:     }

  36:     if (logger.isDebugEnabled()) {

  37:       logger.debug("Url is " + calendarUrl.toString());

  38:     }

  39:   }

  40:  

  41:  

  42:   //get id of correct calendar

  43:   private String getCalendarId() throws IOException, ServiceException {

  44:     String calendarId = null;

  45:     URL metafeedUrl = new URL(METAFEED_URL_BASE + username);

  46:     if (logger.isDebugEnabled()) {

  47:       logger.debug("Url is " + metafeedUrl.toString());

  48:     }

  49:     CalendarFeed resultFeed = service.getFeed(metafeedUrl, CalendarFeed.class);

  50:     for (int i = 0; i < resultFeed.getEntries().size(); i++) {

  51:       CalendarEntry entry = resultFeed.getEntries().get(i);

  52:       if (calendarName.equalsIgnoreCase(entry.getTitle().getPlainText())) {

  53:         calendarId = new File(entry.getId()).getName();

  54:         break;

  55:       }

  56:     }

  57:     return calendarId;

  58:   }

  59:  

I have left out of the above the getters and setters to make it more concise.
Using the above class, you now can access the non primary calendar simply using the syntax:

calendarUtil.getService().insert(…)
or any other service function.