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<title>Java date and time API - Julian calendar system</title> | |
<author>Stephen Colebourne</author> | |
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<body> | |
<section name="Julian calendar system"> | |
<p> | |
The Julian calendar system is calendar system that was widely used from about 4CE to 1582CE. | |
It was replaced by the <a href="cal_gregorian.html">Gregorian</a> calendar on 1582-10-15. | |
The Julian calendar defines a leap year as once every four years. | |
This becomes inaccurate over time, to such an extent that by 1582, 10 days had to be | |
'lost' to correct the calendar. | |
</p> | |
<p> | |
The Julian calendar is represented in Joda-Time by the Julian chronology. | |
This chronology applies Julian rules for all time. | |
Normally, a more accurate historic calendar is found by using the | |
<a href="cal_gj.html">GregorianJulian</a> chronology instead. | |
</p> | |
<p> | |
References | |
<ul> | |
<li>Calendrical Calculations - Millenium Edition - ISBN 0521777526</li> | |
<li><a href="http://en.wikipedia.org/wiki/Julian_calendar">Wikipedia - Julian Calendar</a></li> | |
</ul> | |
</p> | |
</section> | |
<section name="Using Julian chronology in Joda-Time"> | |
<p> | |
Within Joda-Time the Julian calendar system can be used by obtaining an | |
instance of <a href="apidocs/org/joda/time/chrono/JulianChronology.html">JulianChronology</a>. | |
This is normally created using the factory method | |
<a href="apidocs/org/joda/time/chrono/JulianChronology.html#getInstance()">JulianChronology.getInstance()</a>. | |
This is then passed into the constructors of the main date and time classes. | |
</p> | |
<source> | |
// setup date object for the Battle of Hastings in 1066 | |
Chronology chrono = JulianChronology.getInstance(); | |
DateTime dt = new DateTime(1066, 10, 14, 10, 0, 0, 0, chrono); | |
</source> | |
</section> | |
</body> | |
</document> |