Try to do this in bank application. People come 1 hour after they date expired and try to charge them for sooner withdrawal because you calculate with 365.25 not 365 days. You will be kicked, believe me.
Pavel 2010/2/23 Wolfgang Laun <wolfgang.l...@gmail.com>: > On Tue, Feb 23, 2010 at 8:07 AM, djb <dbrownel...@hotmail.com> wrote: >> >> I think though that the majority of uses for a rules engine is in a >> business >> context, where they don't use astronomical time. >> >> If the doctor's orders are: >> "You cannot get out of bed for 2 months" >> >> This means 59 days if he told you February 1st, and it means 62 days if he >> told you July 1st. >> > > This is a particularly bad example, because doctors can't say that - at > least not one I'd trust ;-) > > I'm arguing that you cannot expect a computer program to relieve you from > the burden of defining what you mean by a "duration of one year" (or month). > Some legal rules require a person to have a certain age, and it is (for > humans) > more convenient to decide this on a person's birthday YMD plus an increment > in the Y number. If your application requires you to use an increment in > the year > component of the YMDhms representation of a point in time, then you are > indeed stuck with Calendar and the resulting overhead. (Memoizing > the results of YMDhms +/- n years might speed things up, for the usual > price.) > > But many applications would be satisfied with using a fixed duration for > a year in terms of 365 or 365.25 or some such value. If, for instance, you > have a library, and you must decide to move a book into deep storage > "if it has not been requested for more than a year" you might calculate > this (faster) by adding 356*24*60*60 to the clock value of the last return. > > -W > >> So at least for me, I am going to have to work out a plan that involves >> GregorianCalendar. >> >> -- >> View this message in context: >> http://n3.nabble.com/AGE-problem-tp215215p354847.html >> Sent from the Drools - User mailing list archive at Nabble.com. >> _______________________________________________ >> rules-users mailing list >> rules-users@lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users > > > _______________________________________________ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > _______________________________________________ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users