The implementation of default methods (original) (raw)

Remi Forax forax at univ-mlv.fr
Sat Dec 15 04:24:15 PST 2012

On 12/15/2012 12:42 PM, Doug Lea wrote:

On 12/15/12 01:50, David Holmes wrote:

2. Document "The default implementation behaves as if..." (Or whatever Doug's proposed wording is.) In j.u.c, we always say "is behaviorally equivalent to" but I dropped the "behaviorally" in Map candidate because someone once told me it was overly pedantic :-)

3. Document "The default implementation MUST" Isn't this just the normal spec part, that should precede the default implementation part? I think not. The "normal spec" describes the abstract operation. "The default implementation MUST" specifies the concrete implementation. Sorry, I don't get it. If you say what the method requires and then say what default implementation is behaviorally equivalent to in terms of other methods (or imported functionality), you should in principle be done. The equivalence-based wording is critical though, and requires some hard work (and a little judgement) to get right. AbstractCollection (and other AbstractX's in j.u) specs include some now-regrettable wording saying exactly what they do rather than what they are equivalent to, which has prevented some improvements over the years. While I'm at it: It is currently a nuisance to get javadocs right when you override a method defaulted in AbstractCollection. Usually, no combination of @inheritDoc's will save you from copy/paste/hack to edit out the default implementation description while keeping the main spec. This will probably happen a lot when using defaulted implementations.

that a good reason to have a tag @implementation then you can write

/**

-Doug

Rémi

More information about the lambda-libs-spec-experts mailing list