Re: [jsr-314-open] Method signatures for event handlers

+1 as well, most of the time it's a burden to add the unused event parameter. Cagatay On Jan 22, 2010, at 8:08 PM, Jason Lee wrote: > +1 > > I'd wager that half the time I don't need the parameter I'm required to pass in, so I'd love to this made optional. Officially. > > On 1/22/10 1:57 PM, Andy Schwartz wrote: >> Cay Horstmann wrote: >>> On 01/22/2010 08:52 AM, Kito Mann wrote: >>>> Personally, I don't think there's anything wrong with having a signature >>>> that requires an event listener. Isn't that how most UI toolkits work? >>>> What about Swing or SWT? >>>> >>>> I do understand the desire to have some code completely decoupled, >>>> though. If we make the signature optional, though, I'm afraid that'll be >>>> even more confusing for users. >>> >>> I don't think it is confusing to say "This parameter is optional". Lots of things are optional in JSF. >> >> Yep. Actually, for the nearest equivalent to this use case - h:commandButton's actionListener - we have specified that the ActionEvent is now optional (as of 2.0 I believe). From the tag doc: >> >> >>> The expression must evaluate to a public method that takes an ActionEvent parameter, with a return type of void, or to a public method that takes no arguments with a return type of void. In the latter case, the method has no way of easily knowing where the event came from, but this can be useful in cases where a notification is needed that "some action happened". >> >> >> Given that, my take is that: >> >> 1. Our biggest risk of confusion would be to have the the spec be inconsistent between these cases. >> 2. The behavior specified for actionListener (event parameter is optional) is the preferred behavior. (We intentionally added this behavior in 2.0). >> 3. The fact that Mojarra implements this behavior for f:event's listener attribute as well is a good thing (and probably intentional). >> 4. We should update the spec in our upcoming MR to clarify that the current behavior is by design. >> >> I have logged the following spec issue to track this: >> >> https://javaserverfaces-spec-public.dev.java.net/issues/show_bug.cgi?id=731 >> >> Andy >> >>> The reason you want to make it so is to have a better unit testing story. >>> >>> Cay >>> >> > > > -- > Jason Lee, SCJP > President, Oklahoma City Java Users Group > Senior Java Developer, Sun Microsystems > http://blogs.steeplesoft.com >