Reflection on records

[Tagir Valeev]

Yes, you have to build it from the Babylon repo.

On Mon, Dec 1, 2025, 14:35 David Alayachew <davidalayachew at gmail.com> wrote:

> Thanks @Tagir Valeev <amaembo at gmail.com>.
>
> I am still not great at the stuff Babylon is doing, so I can only roughly
> follow along. Regardless, it sounds like this is depending on Babylon
> features which have not yet landed in the mainline jdk, yes?
>
>
> On Mon, Dec 1, 2025, 5:22 AM Tagir Valeev <amaembo at gmail.com> wrote:
>
>> I think this will surely be possible for RecordComponents with code
>> reflection (project Babylon), using the syntax you propose.
>>
>> You can create a quotable function like this:
>>
>> import jdk.incubator.code.*;
>>
>> @Reflect
>> @FunctionalInterface
>> interface Accessor {
>>   Object get(Record r);
>> }
>>
>> Then create something like (just a sketch, sorry, I have no time now to
>> provide a full-fledged sample):
>>
>> static RecordComponent foo(Accessor acc) {
>>   Quoted q = Op.ofQuotable(acc).orElseThrow();
>>   // extract a method handle from q using Babylon API
>>   // unreflect it and find the corresponding RecordComponent
>> }
>>
>> With best regards,
>> Tagir Valeev
>>
>> On Sat, Nov 29, 2025 at 8:45 PM David Alayachew <davidalayachew at gmail.com>
>> wrote:
>>
>>> Hello @amber-dev <amber-dev at openjdk.org>,
>>>
>>> I asked this on core-libs-dev already, but I figured I should ask here
>>> too.
>>>
>>> Let's say I have some record User(String firstName, String lastName) {}.
>>>
>>> Is there any possible way for me to do the following?
>>>
>>> java.lang.reflect.RecordComponent firstName = foo(User::firstName);
>>>
>>> I'll even accept this.
>>>
>>> java.lang.reflect.Method lastName = foo(User::lastName);
>>>
>>> Thank you for your time and consideration.
>>> David Alayachew
>>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/amber-dev/attachments/20251201/f03e4ecc/attachment.htm>