Reinstate qualifier support for legacy JSR-330 @javax.inject.Named annotation

[marcioscharamtrustly]

Affects: Spring Boot 3.2.5, Spring 6.1.6. Also tested with Spring Boot 3.2.8

We have a project which we have some modules using javax/Guice and others with Spring Boot. Now we're upgrading from Spring Boot 2.7.18 to 3.2.5, but we're having some problems related to javax.inject.Named.

Our code has a "common" module with services/repositories which is used in both Guice and Spring Boot, and for that we're using @Named/@Inject in the classes.

In version 2.7.18 all is working fine, but when we upgraded to 3.2.5 we started receiving an error when injecting dependencies on a class. The class has 2 parameters in the constructor, both of an interface and using @Named("nameOfBean") to distinguish between the expected implementation to be injected, and we have the two related implementations.

I created a simple project to reproduce the problem and share with you. I tried changing some dependencies and nothing solved the problem.
I tried changing all to jakarta.*, and then all worked fine. But, that's not an option right now because of project context.

The project is in https://github.com/marcioscharamtrustly/TestSpringBootJavax

A lille more about the problem: It appears that Spring identifies @Named and knows how to handle and inject it. But it doesn't work well when the parameters expect a @Named("name").

And we're based on this issue: #31090

The error I'm receiving when running TestSpringBootJavaxApplication is:

***************************
APPLICATION FAILED TO START
***************************

Description:

Parameter 0 of constructor in any.javax.code.Service required a single bean, but 2 were found:
	- ONE: defined in file [/Users/marcio.scharam/TestSpringBootJavax/javax-module/target/classes/any/javax/code/OneRepository.class]
	- TWO: defined in file [/Users/marcio.scharam/TestSpringBootJavax/javax-module/target/classes/any/javax/code/TwoRepository.class]

This may be due to missing parameter name information

Action:

Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed

Ensure that your compiler is configured to use the '-parameters' flag.
You may need to update both your build tool settings as well as your IDE.
(See https://github.com/spring-projects/spring-framework/wiki/Upgrading-to-Spring-Framework-6.x#parameter-name-retention)

Process finished with exit code 1

We also tested using maven-compiler-plugin 3.13.0, setting the true as suggested here: https://github.com/spring-projects/spring-framework/wiki/Upgrading-to-Spring-Framework-6.x#parameter-name-retention

[sbrannen]

It looks like we'd need to reintroduce support for javax.inject.Qualifier in QualifierAnnotationAutowireCandidateResolver, like we did for jakarta.inject.Named in #31090.

[sbrannen]

Hi @marcioscharamtrustly,

Congratulations on submitting your first issue for the Spring Framework! 👍

And thanks for the detailed description and sample project.

This has been addressed for inclusion in the upcoming Spring Framework 6.1.12.

[marcioscharamtrustly]

Glad to help and thank you all by the fast analysis and response.