/** * Returns the latest applicable onset of this observance for the specified date. * * @param date the latest date that an observance onset may occur * @return the latest applicable observance date or null if there is no applicable observance * onset for the specified date */ public final Date getLatestOnset(final Date date) { if (initialOnset == null) { try { initialOnset = applyOffsetFrom(calculateOnset(((DtStart) getProperty(Property.DTSTART)).getDate())); } catch (ParseException e) { Log log = LogFactory.getLog(Observance.class); log.error("Unexpected error calculating initial onset", e); // XXX: is this correct? return null; } } // observance not applicable if date is before the effective date of this observance.. if (date.before(initialOnset)) { return null; } if ((onsetsMillisec != null) && (onsetLimit == null || date.before(onsetLimit))) { return getCachedOnset(date); } Date onset = initialOnset; Date initialOnsetUTC; // get first onset without adding TZFROM as this may lead to a day boundary // change which would be incompatible with BYDAY RRULES // we will have to add the offset to all cacheable onsets try { initialOnsetUTC = calculateOnset(((DtStart) getProperty(Property.DTSTART)).getDate()); } catch (ParseException e) { Log log = LogFactory.getLog(Observance.class); log.error("Unexpected error calculating initial onset", e); // XXX: is this correct? return null; } // collect all onsets for the purposes of caching.. final DateList cacheableOnsets = new DateList(); cacheableOnsets.setUtc(true); cacheableOnsets.add(initialOnset); // check rdates for latest applicable onset.. final PropertyList rdates = getProperties(Property.RDATE); for (final Iterator i = rdates.iterator(); i.hasNext(); ) { final RDate rdate = (RDate) i.next(); for (final Iterator j = rdate.getDates().iterator(); j.hasNext(); ) { try { final DateTime rdateOnset = applyOffsetFrom(calculateOnset((Date) j.next())); if (!rdateOnset.after(date) && rdateOnset.after(onset)) { onset = rdateOnset; } /* * else if (rdateOnset.after(date) && rdateOnset.after(onset) && (nextOnset == null || * rdateOnset.before(nextOnset))) { nextOnset = rdateOnset; } */ cacheableOnsets.add(rdateOnset); } catch (ParseException e) { Log log = LogFactory.getLog(Observance.class); log.error("Unexpected error calculating onset", e); } } } // check recurrence rules for latest applicable onset.. final PropertyList rrules = getProperties(Property.RRULE); for (final Iterator i = rrules.iterator(); i.hasNext(); ) { final RRule rrule = (RRule) i.next(); // include future onsets to determine onset period.. final Calendar cal = Dates.getCalendarInstance(date); cal.setTime(date); cal.add(Calendar.YEAR, 10); onsetLimit = Dates.getInstance(cal.getTime(), Value.DATE_TIME); final DateList recurrenceDates = rrule.getRecur().getDates(initialOnsetUTC, onsetLimit, Value.DATE_TIME); for (final Iterator j = recurrenceDates.iterator(); j.hasNext(); ) { final DateTime rruleOnset = applyOffsetFrom((DateTime) j.next()); if (!rruleOnset.after(date) && rruleOnset.after(onset)) { onset = rruleOnset; } /* * else if (rruleOnset.after(date) && rruleOnset.after(onset) && (nextOnset == null || * rruleOnset.before(nextOnset))) { nextOnset = rruleOnset; } */ cacheableOnsets.add(rruleOnset); } } // cache onsets.. Collections.sort(cacheableOnsets); DateTime cacheableOnset = null; this.onsetsMillisec = new long[cacheableOnsets.size()]; this.onsetsDates = new DateTime[onsetsMillisec.length]; for (int i = 0; i < onsetsMillisec.length; i++) { cacheableOnset = (DateTime) cacheableOnsets.get(i); onsetsMillisec[i] = cacheableOnset.getTime(); onsetsDates[i] = cacheableOnset; } return onset; }