How to inject Converter which returns list of generic type in Kotlin?

Question

My application is implemented on Kotlin and I use spring boot 3.

I have a class like this:

import org.springframework.core.convert.converter.Converter

@Component
class MyConverter : Converter<SomeResult, List<UserDto>> {
...
}

I want to inject it(using interface!!!) to another component:

@Service
class MyService(
   private val myConverter : Converter<SomeResult, List<UserDto>>
){
...
}

But I receive the error:

Parameter 1 of constructor in ******.MyService required a bean of type 'org.springframework.core.convert.converter.Converter' that could not be found.

How can I fix it ?

P.S.

This trick perfectly works for converters without generics. For example:

Converter<UserDto, AnotherDto>

P.S.

My problem is I can't autowire by interface

private val myConverter : Converter<SomeResult, List<UserDto>>

As a workaround I can autowire by type(and it works)

private val myConverter : MyConverter 

But it doesn't look perfect from my point of view

Answer 1

If you provide your converter as a @Bean, you should be able to inject this converter (even as an interface)

@Configuration
class MyConfig {
    // return type is interface
    @Bean fun myConverter():Converter<SomeResult, List<UserDto>>  = MyConverter()

}

// @Component <-- does not work 
// provided as Bean in MyConfig <-- works
class MyConverter : Converter<SomeResult, List<UserDto>> {
    override fun convert(source: SomeResult): List<UserDto> {
        return listOf(UserDto())
    }
}

@Service
class MyService(
    private val myConverter : Converter<SomeResult, List<UserDto>>
){
}