On 2/1/11 2:06 PM, Luc Maisonobe wrote: > Le 01/02/2011 18:22, Jörg Schaible a écrit : >> Hi, >> >> Phil Steitz wrote: >> >>> We are in process of redesigning our exceptions hierarchy in [math] >>> and we could use some input / perspective from other Commons >>> community members. Thanks in advance for your feedback and perspective. >>> >>> The most recent attempt at agreeing on design principles is [1] and >>> I have tried to document the points of agreement in a section that I >>> just added to the [math] Developer's Guide [2] (it will take a few >>> hours for this to make it to the live site. The source xdoc is in >>> trunk/src/site/xdoc/developers.xml) >>> >>> The JIRA issue [3] referenced in [1] calls out a specific point on >>> which we are trying to gain consensus in a specific example. >>> >>> The currently defined exceptions in [math] can be found in the >>> top-level package and .exceptions. Those in the top-level have at >>> this point been deprecated. >> Has anyone of you considered the usage of an exception context? We introduce >> this with lang3 (http://commons.apache.org/lang/api-3.0- >> beta/org/apache/commons/lang3/exception/ExceptionContext.html) and it >> basically adds a map with key/value pairs to the exception itself. >> >> This concept has worked out quite nicely especially in situations where code >> can nest deeply in conjunction with user-provided code that make calls in >> the core functionality again. >> >> The nice part is that you can add information at each position that can >> provide useful information (assuming MathException implements this >> interface): > We didn't consider that :-( > It seems very interesting to me. > > What do other think about it ? > Thanks, Jörg!
Very nice idea. I can see added value implementing the interface; but unfortunately I don't see it replacing either the localization / message framework or the hierarchy. For reasons that others have stated, I think that we do need a simple hierarchy. We also need messages that convey more than data values and I am concerned that making sense out of key/value pairs in messages would require brittle convention-maintaining. Have a look at the messages that we maintain today: http://s.apache.org/NNd It could be, though, that the embedded machinery might be useful and allowing users to add data to exception messages is a powerful feature. Phil --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
