Hi Joe, Thanks for your confirmation. Bean Validation may benefit from it, but I understand that just a single request hardly justifies the change.
--Gunnar 2017-01-23 23:05 GMT+01:00 joe darcy <joe.da...@oracle.com>: > Hi Gunnar, > > Annotations went into the platform way back in Java SE 5.0, with a GA during > 2004. When working on repeating annotations, I was surprised to find there > weren't stronger ordering guarantees for annotations from core reflection. > However, requests to tighten this aspect of the platform haven't come up > very often in the interim and I don't like it is likely to happen at this > point. > > HTH, > > -Joe > > > > On 1/17/2017 11:26 PM, Gunnar Morling wrote: >> >> Joseph, all, >> >> Thanks for the clarification. >> >> Are there chances to establish such guaranteed ordering in a future >> Java version? As pointed out, it'd be very helpful to Bean Validation >> and I reckon other cases, too. >> >> Thanks, >> >> --Gunnar >> >> >> >> 2017-01-18 3:13 GMT+01:00 Joseph D. Darcy <joe.da...@oracle.com>: >>> >>> Hello, >>> >>> Following up on Joel's message, IIRC this ordering issue did come up >>> during >>> the design and testing of repeating annotations. >>> >>> As noted previously in the thread, while the ordering of the annotations >>> in >>> a container annotation is guaranteed, there is *not* a general ordering >>> constraint on the annotations returned by the methods of the >>> AnnotatedElement interface. >>> >>> HTH, >>> >>> -Joe >>> >>> >>> On 1/13/2017 1:16 PM, Gunnar Morling wrote: >>>> >>>> Hi Yuri, >>>> >>>> Thanks for the pointer. >>>> >>>> But do you see any clear description of an order mandated for >>>> getDeclaredAnnotations()? The only references to an order I can find >>>> there are for repeatable annotations (where source code order is >>>> maintained when retrieving them via the container annotation type). >>>> But I cannot find any guaranteed order when obtaining all declared >>>> annotations from an element. >>>> >>>> The reason why I'm asking is Bean Validation, where we've seen >>>> requests of people that wish to validate the constraints of an element >>>> in a fixed order, aborting after the first failed constraint: >>>> >>>> @NotNull >>>> @Email >>>> String email; >>>> >>>> Here one may want to first validate @NotNull and don't proceed with >>>> validating @Email if the field is null. >>>> >>>> Relying on source order would be a very natural way to express the >>>> order of constraints. Without a guaranteed ordering of annotations >>>> we'd have to add some other means of ordering, e.g. an attribute with >>>> the index (@NotNull(order=0) @Email(order=1)) which is more verbose of >>>> course. >>>> >>>> --Gunnar >>>> >>>> >>>> >>>> >>>> >>>> 2017-01-13 21:15 GMT+01:00 Yuri Gaevsky <ygaev...@azulsystems.com>: >>>>> >>>>> Hi Gunnar, >>>>> >>>>> Please take a look at JDK-8010679 'Clarify "present" and annotation >>>>> ordering in Core Reflection for Annotations' [*]. >>>>> >>>>> Best regards, >>>>> -Yuri >>>>> >>>>> [*] https://bugs.openjdk.java.net/browse/JDK-8010679 >>>>> >>>>> >>>>> -----Original Message----- >>>>> From: core-libs-dev [mailto:core-libs-dev-boun...@openjdk.java.net] On >>>>> Behalf Of Gunnar Morling >>>>> Sent: Friday, January 13, 2017 08:14 PM >>>>> To: core-libs-dev@openjdk.java.net >>>>> Subject: Guaranteed order of annotations? >>>>> >>>>> Hi, >>>>> >>>>> Is there any order guaranteed in which an element's annotations are >>>>> returned by AnnotatedElement#getDeclaredAnnotations()? Specifically, >>>>> is this the order in which the annotations are given in the source >>>>> code? >>>>> >>>>> Section 9.7.5. of the JLS ("Multiple Annotations of the Same Type") >>>>> makes a statement of the source order being considered by the array of >>>>> the implicit container annotation created for a repeatable annotation >>>>> ("[...] all the base annotations in the left-to-right order in which >>>>> they appeared in the context"). >>>>> >>>>> But I couldn't find any authoritative description on the ordering >>>>> behaviour of getDeclaredAnnotations(). Should we assume that we cannot >>>>> rely on the order in the source? >>>>> >>>>> Thanks for any pointers, >>>>> >>>>> --Gunnar >>> >>> >
