[lang] DateUtils round and truncate functionality with Calendar.AM_PM
Does anyone know how the DateUtils methods round and truncate are suppose to behave when passed Calendar.AM_PM? I've tried several combinations of round, and they all seem to truncate instead. There is nothing in the Javadocs for these methods about the expected result, and I'm not able to tell if the methods are working properly. Steven Caswell [EMAIL PROTECTED] In our own native land, in defense of the freedom that is our birthright, and which we ever enjoyed till the late violation of it -- for the protection of our property, acquired solely by the honest industry of our fore-fathers and ourselves, against violence actually offered, we have taken up arms. We shall lay them down when hostilities shall cease on the part of the aggressors, and all danger of their being renewed shall be removed, and not before. - Thomas Jefferson
Re: [lang] DateUtils round and truncate functionality with Calendar.AM_PM
I don't know what it should do offhand. Perhaps you could suggest sensible behaviour? Stephen - Original Message - From: Steven Caswell [EMAIL PROTECTED] Does anyone know how the DateUtils methods round and truncate are suppose to behave when passed Calendar.AM_PM? I've tried several combinations of round, and they all seem to truncate instead. There is nothing in the Javadocs for these methods about the expected result, and I'm not able to tell if the methods are working properly. Steven Caswell [EMAIL PROTECTED] In our own native land, in defense of the freedom that is our birthright, and which we ever enjoyed till the late violation of it -- for the protection of our property, acquired solely by the honest industry of our fore-fathers and ourselves, against violence actually offered, we have taken up arms. We shall lay them down when hostilities shall cease on the part of the aggressors, and all danger of their being renewed shall be removed, and not before. - Thomas Jefferson - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: [lang] DateUtils round and truncate functionality with Calendar.AM_PM
I don't know that rounding to AM_PM makes sense. I'm having a difficult time coming up with any rounding scenario that makes sense. I think it makes sense to say that the boundary is 12:00PM, and that times before that value cause round down, and times after that value cause round up. But what does round down mean? What does round up mean? Maybe someone who has a use case for this functionality can provide a good suggestion. Steven Caswell [EMAIL PROTECTED] a.k.a Mungo Knotwise of Michel Delving One ring to rule them all, one ring to find them... -Original Message- From: Stephen Colebourne [mailto:[EMAIL PROTECTED] Sent: Sunday, August 03, 2003 6:32 PM To: Jakarta Commons Developers List; [EMAIL PROTECTED] Subject: Re: [lang] DateUtils round and truncate functionality with Calendar.AM_PM I don't know what it should do offhand. Perhaps you could suggest sensible behaviour? Stephen - Original Message - From: Steven Caswell [EMAIL PROTECTED] Does anyone know how the DateUtils methods round and truncate are suppose to behave when passed Calendar.AM_PM? I've tried several combinations of round, and they all seem to truncate instead. There is nothing in the Javadocs for these methods about the expected result, and I'm not able to tell if the methods are working properly. Steven Caswell [EMAIL PROTECTED] In our own native land, in defense of the freedom that is our birthright, and which we ever enjoyed till the late violation of it -- for the protection of our property, acquired solely by the honest industry of our fore-fathers and ourselves, against violence actually offered, we have taken up arms. We shall lay them down when hostilities shall cease on the part of the aggressors, and all danger of their being renewed shall be removed, and not before. - Thomas Jefferson - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [lang] DateUtils round and truncate functionality with Calendar.AM_PM
Steven Caswell wrote: I don't know that rounding to AM_PM makes sense. I'm having a difficult time coming up with any rounding scenario that makes sense. I think it makes sense to say that the boundary is 12:00PM, and that times before that value cause round down, and times after that value cause round up. But what does round down mean? What does round up mean? Maybe someone who has a use case for this functionality can provide a good suggestion. Here's how I approached most of this logic... I treated truncating and rounding functions as eliminating all units below this order of specificity. How to apply this to AM_PM? Well, you'd keep the day unit and drop the hours unit. So aside from the date, the two possible values are: AM, 0 hours, 0 minutes, 0 sec, 0 ms. PM, 0 hours, 0 minutes, 0 sec, 0 ms. The first case is somewhat straight-forward... 0 hour is equivalent to 12:00 AM. The second case is a bit more confusing, but to be parallel, I would say it should be 12:00 PM. So truncating would have 12:00 AM to 11:59:59.999 AM - 12:00 AM, and 12:00 PM to 11:59:59.999 PM - 12:00 PM. Rounding would then have 6:00 PM to 5:59:59.999 AM - 12:00 AM and 6:00 AM to 5:59:59.999 PM - 12:00 PM. (I believe our convention is to always round up, so 6:00 AM - 12:00 PM). Does this make sense? Probably not a very commonly used case, but seems like we should have predictable behavior is someone passes this unit. Or conversely it could throw an exception with an unanticipated time unit? -- Serge Knystautas President Lokitech software . strategy . design http://www.lokitech.com/ p. 1.301.656.5501 e. [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [lang] DateUtils round and truncate functionality with Calendar.AM_PM
Best guess: roundDown 01:30 goes to 00:00 roundUp 01:30 goes to 12:00 roundDown 13:30 goes to 12:00 roundUp 13:30 goes to 00:00 next day Stephen - Original Message - From: Steven Caswell [EMAIL PROTECTED] To: 'Jakarta Commons Developers List' [EMAIL PROTECTED] Sent: Monday, August 04, 2003 12:45 AM Subject: RE: [lang] DateUtils round and truncate functionality with Calendar.AM_PM I don't know that rounding to AM_PM makes sense. I'm having a difficult time coming up with any rounding scenario that makes sense. I think it makes sense to say that the boundary is 12:00PM, and that times before that value cause round down, and times after that value cause round up. But what does round down mean? What does round up mean? Maybe someone who has a use case for this functionality can provide a good suggestion. Steven Caswell [EMAIL PROTECTED] a.k.a Mungo Knotwise of Michel Delving One ring to rule them all, one ring to find them... -Original Message- From: Stephen Colebourne [mailto:[EMAIL PROTECTED] Sent: Sunday, August 03, 2003 6:32 PM To: Jakarta Commons Developers List; [EMAIL PROTECTED] Subject: Re: [lang] DateUtils round and truncate functionality with Calendar.AM_PM I don't know what it should do offhand. Perhaps you could suggest sensible behaviour? Stephen - Original Message - From: Steven Caswell [EMAIL PROTECTED] Does anyone know how the DateUtils methods round and truncate are suppose to behave when passed Calendar.AM_PM? I've tried several combinations of round, and they all seem to truncate instead. There is nothing in the Javadocs for these methods about the expected result, and I'm not able to tell if the methods are working properly. Steven Caswell [EMAIL PROTECTED] In our own native land, in defense of the freedom that is our birthright, and which we ever enjoyed till the late violation of it -- for the protection of our property, acquired solely by the honest industry of our fore-fathers and ourselves, against violence actually offered, we have taken up arms. We shall lay them down when hostilities shall cease on the part of the aggressors, and all danger of their being renewed shall be removed, and not before. - Thomas Jefferson - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
