BigDate : Java Glossary
©1996-2017 Roedy Green of Canadian Mind Products
Canadian Mind Products replacement forthe notorious standard java.util.Date class.
BigDate converts back and forth between Julian (days since 1970 Jan 01) and Gregorian (yyyy mm dd) forms. BigDate handles dates
from 999,999 BC to 999,999 AD. It
handles the following calendar anomalies:
BigDate differs from Oracle’s Date in that it handles
dates prior to 1970 and it uses Julian day numbers
relative to 1970 Jan 01 rather than millisecond timestamps.
BigDate uses 4, 5 or 6-digit years rather than 2-digit
years like Oracle’s Date. Month 01=January as is traditional, unlike Oracle’s
Date which uses 00=Jan. Similarly, the first of the month is 01 not 00 as in
Oracle’s Date class. For example here is how you could compute the day after a
There are many more examples in the TestDate.java class that comes with BigDate. BigDate is a bit of a misnomer,
BigDate objects are smaller and faster than java.util.Date or
objects. I called them BigDate s because they can
accurately handle a wider range of date than the Java classes.
- missing year 0.
- missing 10 days in 1582 from
1582-10-05 to 1582-10-14.
- the change in leap year rule calculation in 1600.
- leaps every 4 years, except every 100, except every 400.