MapStruct using interface with Spring Boot causes NoSuchBeanDefinitionException

Question

I have implemnted an interface for using MapStruct:

@Mapper(componentModel = "spring")
public interface MapStructMapper {

    MapStructMapper INSTANCE = Mappers.getMapper( MapStructMapper.class );

    MyApiModel myInternalClassToMyApiModel(MyDocument.MyInternalClass myInternalClass);
    MyDocument.MyInternalClass myApiModelToMyInternalClass(MyApiModel myApiModel);
}

When running the gradle build I get the following exception when tests are executed:

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'MapStructMapper' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

In my test class I currently have only:

@Autowired
protected MapStructMapper mapper;

and in my build.gradle

implementation 'org.mapstruct:mapstruct:1.4.2.Final'
annotationProcessor 'org.mapstruct:mapstruct-processor:1.4.2.Final'

How can I solve this problem and how can I invoke the mapping if I use MapStruct using an interface?

Answer 1

Based on the information you provided, it's hard to give a definitive answer.

Please check that you not only included the mapstruct dependencies but also the annotation processor in your build such that the MapStructMapperImpl is actually generated.

If it is indeed generated, you must make sure that it is included in the application context of your test. If you use @SpringBootTest, you need to make sure that the interface is declared in a package that is scanned by the component scan. If you construct a dedicated context with @ContextConfiguration, you need to list MapStructMapperImpl.class in the list that you pass to the parameter classes like you would with other classes annotated with @Component.