net.fortuna.ical4j.model.component.Observance Maven / Gradle / Ivy
/**
* Copyright (c) 2012, Ben Fortuna
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* o Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* o Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* o Neither the name of Ben Fortuna nor the names of any other contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package net.fortuna.ical4j.model.component;
import net.fortuna.ical4j.model.*;
import net.fortuna.ical4j.model.property.*;
import net.fortuna.ical4j.util.TimeZones;
import net.fortuna.ical4j.validate.ComponentValidator;
import net.fortuna.ical4j.validate.ValidationException;
import net.fortuna.ical4j.validate.ValidationRule;
import net.fortuna.ical4j.validate.Validator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.time.*;
import java.time.temporal.ChronoUnit;
import java.time.temporal.Temporal;
import java.util.*;
import static net.fortuna.ical4j.model.Property.*;
import static net.fortuna.ical4j.validate.ValidationRule.ValidationType.One;
/**
* $Id$ [05-Apr-2004]
*
* Defines an iCalendar sub-component representing a timezone observance. Class made abstract such that only Standard
* and Daylight instances are valid.
*
* @author Ben Fortuna
*/
public abstract class Observance extends Component {
/**
*
*/
private static final long serialVersionUID = 2523330383042085994L;
/**
* one of 'standardc' or 'daylightc' MUST occur and each MAY occur more than once.
*/
public static final String STANDARD = "STANDARD";
/**
* Token for daylight observance.
*/
public static final String DAYLIGHT = "DAYLIGHT";
private final Validator validator = new ComponentValidator<>(
new ValidationRule<>(One, TZOFFSETFROM, TZOFFSETTO, DTSTART)
);
// TODO: clear cache when observance definition changes (??)
private long[] onsetsMillisec;
private OffsetDateTime[] onsetsDates;
// private Map onsets = new TreeMap();
private OffsetDateTime initialOnset = null;
/**
* Used for parsing times in a UTC date-time representation.
*/
private static final String UTC_PATTERN = "yyyyMMdd'T'HHmmss";
private static final DateFormat UTC_FORMAT = new SimpleDateFormat(UTC_PATTERN);
static {
UTC_FORMAT.setTimeZone(TimeZones.getUtcTimeZone());
UTC_FORMAT.setLenient(false);
}
/* If this is set we have rrules. If we get a date after this rebuild onsets */
private Instant onsetLimit;
/**
* Constructs a timezone observance with the specified name and no properties.
*
* @param name the name of this observance component
*/
protected Observance(final String name) {
super(name);
}
/**
* Constructor protected to enforce use of sub-classes from this library.
*
* @param name the name of the time type
* @param properties a list of properties
*/
protected Observance(final String name, final PropertyList properties) {
super(name, properties);
}
/**
* {@inheritDoc}
*/
@Override
public final void validate(final boolean recurse) throws ValidationException {
validator.validate(this);
// From "4.8.3.3 Time Zone Offset From":
// Conformance: This property MUST be specified in a "VTIMEZONE"
// calendar component.
// From "4.8.3.4 Time Zone Offset To":
// Conformance: This property MUST be specified in a "VTIMEZONE"
// calendar component.
/*
* ; the following are each REQUIRED, ; but MUST NOT occur more than once dtstart / tzoffsetto / tzoffsetfrom /
*/
/*
* ; the following are optional, ; and MAY occur more than once comment / rdate / rrule / tzname / x-prop
*/
if (recurse) {
validateProperties();
}
}
/**
* 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 OffsetDateTime getLatestOnset(final Temporal date) {
if (date instanceof LocalDate) {
throw new UnsupportedOperationException("Unable to get timezone observance for date-only temporal.");
}
TzOffsetTo offsetTo;
try {
offsetTo = getProperties().getRequired(TZOFFSETTO);
} catch (ConstraintViolationException e) {
Logger log = LoggerFactory.getLogger(Observance.class);
log.error("Unexpected error calculating latest onset", e);
return null;
}
OffsetDateTime offsetDate = LocalDateTime.ofInstant(Instant.from(date), ZoneOffset.UTC).atOffset(
offsetTo.getOffset());
if (initialOnset == null) {
try {
DtStart dtStart = getProperties().getRequired(DTSTART);
initialOnset = LocalDateTime.from(dtStart.getDate()).atOffset(offsetTo.getOffset());
} catch (ConstraintViolationException e) {
Logger log = LoggerFactory.getLogger(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 (TemporalAdapter.isBefore(offsetDate, initialOnset)) {
return null;
}
if ((onsetsMillisec != null) &&
(onsetLimit == null || TemporalAdapter.isBefore(offsetDate, onsetLimit))) {
return getCachedOnset(offsetDate);
}
OffsetDateTime onset = initialOnset;
// 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
Optional> startDate = getProperties().getFirst(DTSTART);
// collect all onsets for the purposes of caching..
final List cacheableOnsets = new ArrayList<>();
cacheableOnsets.add(initialOnset);
// check rdates for latest applicable onset..
Optional offsetFrom = getProperties().getFirst(TZOFFSETFROM);
final List rdates = getProperties().get(RDATE);
for (Property rdate : rdates) {
List rdateDates = ((RDate) rdate).getDates();
for (final LocalDateTime rdateDate : rdateDates) {
final OffsetDateTime rdateOnset = OffsetDateTime.from(rdateDate.atOffset(offsetFrom.get().getOffset()));
if (!rdateOnset.isAfter(offsetDate) && rdateOnset.isAfter(onset)) {
onset = rdateOnset;
}
/*
* else if (rdateOnset.after(date) && rdateOnset.after(onset) && (nextOnset == null ||
* rdateOnset.before(nextOnset))) { nextOnset = rdateOnset; }
*/
cacheableOnsets.add(rdateOnset);
}
}
// check recurrence rules for latest applicable onset..
final List rrules = getProperties().get(RRULE);
for (Property rrule : rrules) {
// include future onsets to determine onset period..
onsetLimit = Instant.from(offsetDate.plus(10, ChronoUnit.YEARS));
final List recurrenceDates = ((RRule) rrule).getRecur().getDates(initialOnset, onsetLimit);
for (final Temporal recurDate : recurrenceDates) {
final OffsetDateTime rruleOnset = OffsetDateTime.from(recurDate).plus(
offsetFrom.get().getOffset().getTotalSeconds(), ChronoUnit.SECONDS);
if (!rruleOnset.isAfter(offsetDate) && rruleOnset.isAfter(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);
OffsetDateTime cacheableOnset;
this.onsetsMillisec = new long[cacheableOnsets.size()];
this.onsetsDates = new OffsetDateTime[onsetsMillisec.length];
for (int i = 0; i < onsetsMillisec.length; i++) {
cacheableOnset = cacheableOnsets.get(i);
onsetsMillisec[i] = cacheableOnset.toInstant().toEpochMilli();
onsetsDates[i] = cacheableOnset;
}
return onset;
}
/**
* Returns a cached onset for the specified date.
*
* @param date
* @return a cached onset date or null if no cached onset is applicable for the specified date
*/
private OffsetDateTime getCachedOnset(final Temporal date) {
int index = Arrays.binarySearch(onsetsMillisec, Instant.from(date).toEpochMilli());
if (index >= 0) {
return onsetsDates[index];
} else {
int insertionIndex = -index - 1;
return onsetsDates[insertionIndex - 1];
}
}
/**
* Returns the mandatory dtstart property.
*
* @return the DTSTART property or null if not specified
* @deprecated use {@link Observance#getProperty(String)}
*/
@Deprecated
public final Optional> getStartDate() {
return getProperty(DTSTART);
}
/**
* Returns the mandatory tzoffsetfrom property.
*
* @return the TZOFFSETFROM property or null if not specified
* @deprecated use {@link Observance#getProperty(String)}
*/
@Deprecated
public final Optional getOffsetFrom() {
return getProperty(TZOFFSETFROM);
}
/**
* Returns the mandatory tzoffsetto property.
*
* @return the TZOFFSETTO property or null if not specified
* @deprecated use {@link Observance#getProperty(String)}
*/
@Deprecated
public final Optional getOffsetTo() {
return getProperty(TZOFFSETTO);
}
}
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