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  <title>Java date and time API - Julian calendar system</title>
  <author>Stephen Colebourne</author>
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<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="https://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>

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