Dominique Devienne wrote: > Let's turn around your question: Tell me of a (string) role (beside the > special task/type cases) that would not be an interface? What good a bean > is, if it's not of an expected Java type? What method or field are you > going to use/call on it?
Any role. Just like you can put any java class with an execute() method in a "task" role, or any java bean in a "datatype" role. Interfaces are fine - they define a set of methods and contract that a class must support. But it is perfectly possible to support the contract without implementing the interface. In JDK1.3+ ( and JMX1.2+) you can use a proxy that implement the interface - but what really matters is the contract, not the syntactic detail. Ant ( and JMX ) have allways had a "loose coupling" aproach. You can write a lot of tasks without having any dependency on ant. > I agree with Costin, all tasks/types become simply beans. You should be > able to use any one of these beans in any place it's suitable to use it, > i.e. any time the Java type/role requested is part of the bean's type (in > the isAssigneableFrom() sense). I agree with you that "roles" should be associated with an interface. I don't agree that the components need to actually implement the interface, they only need to support the contract. I would like to allow any mbean that has an "execute" method to be used as an ant task. Or any mbean that supports a particular contract to be used in the associated role - without having to change the mbean and make it depend on ant. > The type being requested depends on who requests it. Inside or outside > targets, it's any bean. And I mean really any bean: Doesn't need to Exactly. > implement anything Ant-related. This is implicitly what we call today a > datatype, and they can be id'd. The subset of these beans that also have > an execute method are also implicitly tasks. The different subsets of > these beans that implements FileSelector are suitable to use within > filesets, and tasks deriving from MatchingTask since we're talking about > it. > > I fail to see what is wrong with this scenario. --DD I think it is a good scenario, and the JMX uses prove it is viable. You may like or dislike Jboss - but their modularity and flexibility ( given by JMX and the low-coupling ) is a proven thing. Costin > > -----Original Message----- > From: Stefan Bodewig [mailto:[EMAIL PROTECTED] > Sent: Wednesday, April 23, 2003 11:12 AM > To: [EMAIL PROTECTED] > Subject: Re: antlib > > On Wed, 23 Apr 2003, Dominique Devienne <[EMAIL PROTECTED]> wrote: > >> Forcing roles to map to an interface is probably a *good* idea! > > Maybe, hmm, probably, not convinced ... > >> Every single bean would become implicitly a data-type, and the ones >> with an execute() method implicitly become tasks. Beyond that, all >> other roles are interfaces. > > How would you have a task that also is a condition? It implements > Condition and has an execute method? > > [DD] Yes! What's wrong with that? > > How would you have a datatype that also is a condition? This may be > far-fetched, not sure. > > Stefan
