/**
* A Chronology in which each year has exactly 360 days of 12 equal months ({@literal i.e.} each
* month has exactly 30 days). This calendar system is used in many climate simulations. There are
* no leap years.
*
* <p>In this Chronology, a millisecond instant of zero corresponds with 1970-01-01T00:00:00.000Z
* and a year has a fixed number of milliseconds (1000*60*60*24*360).
*
* <p>There is no concept of an era in this calendar, so all durations and fields relating to this
* concept are not supported. Additionally, the concept of a "weekyear" (the year that "owns" a
* given week) is not implemented.
*
* <p>Instances of this class can only be created in {@link DateTimeZone#UTC}. (Support for time
* zones makes little sense in this chronology).
*
* <p>Instances of this class are immutable.
*
* @author Jon Blower
* @see http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.4/cf-conventions.html#calendar
*/
public final class ThreeSixtyDayChronology extends FixedYearLengthChronology {
///// DURATIONS /////
/** 30 days in every month */
private final DurationField monthDuration =
new PreciseDurationField(DurationFieldType.months(), 30 * this.days().getUnitMillis());
private final DateTimeField dayOfMonth =
new OneBasedPreciseDateTimeField(
DateTimeFieldType.dayOfMonth(), this.days(), this.monthDuration);
private final DateTimeField monthOfYear =
new OneBasedPreciseDateTimeField(
DateTimeFieldType.monthOfYear(), this.monthDuration, this.years());
///// CONSTRUCTORS AND FACTORIES /////
private static final ThreeSixtyDayChronology INSTANCE_UTC = new ThreeSixtyDayChronology();
/** Private constructor to prevent direct instantiation */
private ThreeSixtyDayChronology() {
super(360);
}
/** Gets an instance of this Chronology in the UTC time zone */
public static ThreeSixtyDayChronology getInstanceUTC() {
return INSTANCE_UTC;
}
///// DURATION ACCESSORS /////
/** Each month has exactly 30 days */
@Override
public DurationField months() {
return this.monthDuration;
}
///// DATE-TIME FIELD ACCESSORS /////
@Override
public DateTimeField dayOfMonth() {
return this.dayOfMonth;
}
@Override
public DateTimeField monthOfYear() {
return this.monthOfYear;
}
@Override
public String toString() {
return "360-day Chronology in UTC";
}
}
/** Private method called from constructor. */
private void setPeriodInternal(
int years, int months, int weeks, int days, int hours, int minutes, int seconds, int millis) {
int[] newValues = new int[size()];
checkAndUpdate(DurationFieldType.years(), newValues, years);
checkAndUpdate(DurationFieldType.months(), newValues, months);
checkAndUpdate(DurationFieldType.weeks(), newValues, weeks);
checkAndUpdate(DurationFieldType.days(), newValues, days);
checkAndUpdate(DurationFieldType.hours(), newValues, hours);
checkAndUpdate(DurationFieldType.minutes(), newValues, minutes);
checkAndUpdate(DurationFieldType.seconds(), newValues, seconds);
checkAndUpdate(DurationFieldType.millis(), newValues, millis);
iValues = newValues;
}
private void testAdd(Date start, DurationFieldType type, int amt, Date end) {
DateTime dtStart = new DateTime(start, ISOChronology.getInstanceUTC());
DateTime dtEnd = new DateTime(end, ISOChronology.getInstanceUTC());
assertEquals(dtEnd, dtStart.withFieldAdded(type, amt));
assertEquals(dtStart, dtEnd.withFieldAdded(type, -amt));
DurationField field = type.getField(ISOChronology.getInstanceUTC());
int diff = field.getDifference(dtEnd.getMillis(), dtStart.getMillis());
assertEquals(amt, diff);
if (type == DurationFieldType.years()
|| type == DurationFieldType.months()
|| type == DurationFieldType.days()) {
LocalDate ymdStart = new LocalDate(start, ISOChronology.getInstanceUTC());
LocalDate ymdEnd = new LocalDate(end, ISOChronology.getInstanceUTC());
assertEquals(ymdEnd, ymdStart.withFieldAdded(type, amt));
assertEquals(ymdStart, ymdEnd.withFieldAdded(type, -amt));
}
}
public void testAddMonths() {
DateTimeFormat format = DateTimeFormat.getFormat("YYYY-MM-DD");
Date startDate = format.parse("1582-01-01");
Date endDate = format.parse("1582-02-01");
testAdd(startDate, DurationFieldType.months(), 1, endDate);
startDate = format.parse("1582-01-01");
endDate = format.parse("1582-07-01");
testAdd(startDate, DurationFieldType.months(), 6, endDate);
startDate = format.parse("1582-01-01");
endDate = format.parse("1583-01-01");
testAdd(startDate, DurationFieldType.months(), 12, endDate);
startDate = format.parse("1582-11-15");
endDate = format.parse("1582-12-15");
testAdd(startDate, DurationFieldType.months(), 1, endDate);
startDate = format.parse("1582-09-04");
endDate = format.parse("1582-11-04");
testAdd(startDate, DurationFieldType.months(), 2, endDate);
startDate = format.parse("1582-09-05");
endDate = format.parse("1582-11-05");
testAdd(startDate, DurationFieldType.months(), 2, endDate);
startDate = format.parse("1582-09-10");
endDate = format.parse("1582-11-10");
testAdd(startDate, DurationFieldType.months(), 2, endDate);
startDate = format.parse("1582-09-15");
endDate = format.parse("1582-11-15");
testAdd(startDate, DurationFieldType.months(), 2, endDate);
startDate = format.parse("1580-01-01");
endDate = format.parse("1584-01-01");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
startDate = format.parse("1580-02-29");
endDate = format.parse("1584-02-29");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
startDate = format.parse("1580-10-01");
endDate = format.parse("1584-10-01");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
startDate = format.parse("1580-10-10");
endDate = format.parse("1584-10-10");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
startDate = format.parse("1580-10-15");
endDate = format.parse("1584-10-15");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
startDate = format.parse("1580-12-31");
endDate = format.parse("1584-12-31");
testAdd(startDate, DurationFieldType.months(), 48, endDate);
}
