I added PredicateDecorator marker interface. Stephen ----- Original Message ----- From: "Sandor Murakozi" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, May 19, 2004 10:49 AM Subject: Re: [collections] [PATCH] Commons Collections - Wrapper and
> Hi Stephen, > > I also think a kind marker interface would be nice. If > someone wants to > travel a tree of predicates (which is needed to display it's > structure, save it, almost anything except building and > simply invoking it) then it would be extremely useful. It > would be also handy if you want to handle different types of > Predicates differently. I think a great part of Predicate > users will need some similar functionality (including me in > my actual project :-)). Now we have to create our reflection > based solution, or huge if else-if statements (brrrrr) , so > I would vote on marker interfaces. > > And yes, it would probably open the door, but is it really a > problem? (I use only predicates at this time, so I'm not a > transformer expert, but I can imagine transformer users with > the same problem then me). > > BR, > don > > >Thank you for your patch. > > >I'm not certain as to how to procede on this one. There is > nothing wrong > >with your patch or idea. The problem is that it opens the > door to accessing > >other functors such as Transformer and Closure. How far > does this go? > > >One idea I have considered is to have a single generic > Decorator interface > >that specifies one method which returns a predicate. > > >Another idea is to use reflection, with a single method on > PredicateUtils to > >access this functionality. This might be less intrusive, > but perhaps is also > >less obvious. > > >Not sure, any opinions? > > >Stephen > > >----- Original Message ----- > >From: "Brian Lloyd-Newberry" <[EMAIL PROTECTED]> > >To: <[EMAIL PROTECTED]> > >Sent: Friday, May 14, 2004 6:38 PM > >Subject: [PATCH] Commons Collections - Wrapper and > Composite >Predicates > > > > Commons Collections developers, > > > > In looking at the 3.1-dev source I see that some > implementations of > > the Predicate objects have: > > Predicate getPredicate() > > or > > Predicate[] getPredicates() > > methods. This is a good thing for me, as I am developing a > search > > interface and would like to be able to use predicates in the > > search/filter process, and be able to do a display of the > predicate > > expression structure. > > > > I observe that there are basic types of predicates. > Ones which > > operate on Objects, ones that operate on a single > (sub)Predicate and > > ones which operate on more than one Predicate. I propose > that the single > > and multiple cases be tagged using an interface so that > the appropriate > > getPredicate() or getPredicates() method can be found. > > > > I have attached a patch and 2 new interfaces > (WrapperPredicate.java > > and CompositePredicate.java) which provide the > functionality I propose. > > WrapperPredicate declares Predicate getPredicate(). > CompositePredicate > > declares Iterator predicates(), shielding the > CompositePredicate from > > modification (the Iterator returned is Unmodifiable) that the > > Predicate[] getPredicates[] implementation would allow > unless a > > defensive copy was made before the return took place. > > > > If you have any questions or concerns about my > implementation please > > let me know. This is my first patch on a Jakarta project, > so I hope I > > have done everything correctly (cvs diff -u). > > > > Thank you for your work and for providing such a useful > library of > > collections to the community. > > > > -Brian > > > > Brian S. Lloyd-Newberry > > Software Engineer > > RBS, Inc > > http://www.rbs2000.com > > > > --------------------------------------------------------------------- > 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]
