@RestController
@RequestMapping("/test")
public class EchoCtrl {
    private static final Logger LOG= LoggerFactory.getLogger(EchoCtrl.class);

    @Autowired
    IServiceForFree serviceForFree;

    @GetMapping(value = "echo") //tag_static
    public SimpleEntity get(@RequestParam(required = false) String name) {
        return new SimpleEntity(name);
    }

    @GetMapping(value = "dynamic") //tag_dynamic
    public SimpleEntity getDynamic(@RequestParam(required = false) String name) {
        // бин с динамически подключаемым сервисом спринга
        DynamicEntity dynamicEntity = new DynamicEntity(); 
        return dynamicEntity.getSimpleEntity(name);
    }

    @GetMapping(value = "spring") //tag_spring
    public String getSpringBean(@RequestParam(required = false) String name) {
        return serviceForFree.getVal(name);
    }
}

@Service
public class ServiceForFree implements IServiceForFree {

    @Override
    public String getVal(String input) {
        return "modified " + input;
    }
}

@Configurable(preConstruction = true, autowire = Autowire.BY_TYPE, dependencyCheck = true)
public class DynamicEntity {
    @Autowired
    IServiceForFree serviceForFree;

    public SimpleEntity getSimpleEntity(String val) {
        return new SimpleEntity(serviceForFree.getVal(val));
    }
}

public class SimpleEntity {
    private String name;

    public SimpleEntity(@NotNull String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }
}