How do I tell Mapstruct to inject a Bean on the generated class?

Question

I am writing a mapper with basic dto -> entity and vice versa. For a specific field, response , I need to invoke Gson's toJson() and fromJson() methods. By using an expression I was able to generate the needed code in the impl class. However I can't find a way to 'tell' mapstruct to inject the bean I need.

Sample code :

@Mapper(componentModel = SPRING, injectionStrategy = InjectionStrategy.CONSTRUCTOR)
public interface ConfigurationMapper {
    
    @Mapping(target = "response", expression = "java(gson.toJson(configurationDTO.getResponse()))")
    MockConfiguration toEntity(ConfigurationDTO configurationDTO);

    @Mapping(target = "response", expression = "java(gson.fromJson(configuration.getResponse(),Object.class))")
    ConfigurationDTO toDTO(MockConfiguration configuration);

    List<ConfigurationDTO> toDTOList(Collection<MockConfiguration> configurations);
}

The Gson config

@Configuration
public class MapperConfiguration {

    @Bean
    public  Gson gson() {
        return new GsonBuilder().setPrettyPrinting().disableHtmlEscaping()
                .setDateFormat("yyyy-MM-dd'T'HH:mm:ssz").registerTypeAdapter(LocalDateTime.class, new LocalDateAdapter())
                .create();
    }
}

@Generated(
    value = "org.mapstruct.ap.MappingProcessor",
    comments = "version: 1.4.2.Final, compiler: javac, environment: Java 11.0.17 (Amazon.com Inc.)"
)
@Component
public class ConfigurationMapperImpl implements ConfigurationMapper {

// I want this to be generated here
    @Autowired
    Gson gson;
//
    @Override
    public MockConfiguration toEntity(ConfigurationDTO configurationDTO) {
        if ( configurationDTO == null ) {
            return null;
        }

        MockConfiguration mockConfiguration = new MockConfiguration();

        mockConfiguration.setId( configurationDTO.getId() );
        mockConfiguration.setPath( configurationDTO.getPath() );
        mockConfiguration.setStatusCode( configurationDTO.getStatusCode() );
        mockConfiguration.setMethod( configurationDTO.getMethod() );

        mockConfiguration.setResponse( gson.toJson(configurationDTO.getResponse()) );

        return mockConfiguration;
    }
    .
    .
    .
}

Any ideas? Don't mind the InjectionStrategy etc in my Mapper, I was trying things that maybe would generate the injection I needed.

How do I tell Mapstruct to inject a Bean on the generated class?

0 Answers0