Spring Bean is not autowired

Question

I have a problem with Spring bean DefaultConfigurationService initialization that is extended from abstract class. I am totally stuck.

Class hiearchy is as follows:

public interface ConfigurationService {
    TaxPayer getTaxPayer();
} 

This class is mentioned to be useful for services that need to be initialized:

public abstract class BaseInitializationAwareService {

    private boolean initialized = false;

    public abstract void initialize();

    protected void checkInitialization() {
        if (!initialized) {
            initialize();
        }
    }

    protected void setInitialized() {
        this.initialized = true;
    }
}

This class acts as base class for Configuration service.

public abstract class BaseConfigurationService extends BaseInitializationAwareService implements ConfigurationService {


}

And with this bean, that acts as a configuration service, is a problem:

    public class DefaultConfigurationService extends BaseConfigurationService {

        private TaxPayerService taxPayerService;

        @Autowired
        public void setTaxPayerService(TaxPayerService taxPayerService) {
            Assert.notNull(taxPayerService);
            this.taxPayerService = taxPayerService;
        }

public void initialize() {
        Optional<TaxPayer> dbtaxPayer = taxPayerService.getActiveTaxPayer();
        if (!dbtaxPayer.isPresent()) {
            throw new IllegalStateException("Tax payer setting not found!");
        }
        this.taxPayer = dbtaxPayer.get();
        setInitialized();
    }

    // the rest omitted...
    }

when I'm creating DefaultConfigurationService bean:

@Bean
    public BaseConfigurationService configurationService() {
        DefaultConfigurationService configurationService = new DefaultConfigurationService();
        configurationService.initialize();
        return configurationService;
    }

then taxPayerService in DefaultConfigurationService is null - it seems that is not autowired.

Can it be connected to the fact that DefaultConfigurationService is extended from abstract class?

TaxPayer service bean:

@Bean
    public TaxPayerService taxPayerService() {
        DatabaseTaxPayerService taxPayer = new DatabaseTaxPayerService();
        return taxPayer;
    }

This bean is probably never initialized...

Thats is a exception:

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'webSecurityConfig.ApiSecurity': Unsatisfied dependency expressed through method 'setContentNegotationStrategy' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration': Unsatisfied dependency expressed through method 'setConfigurers' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'passwordRecoverController': Unsatisfied dependency expressed through method 'setUserService' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'defaultUserService': Unsatisfied dependency expressed through method 'setNotificationService' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'notificationService': Unsatisfied dependency expressed through method 'setConfigurationService' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'configurationService' defined in class path resource [com.example.config/AppConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.example.services.BaseConfigurationService]: Factory method 'configurationService' threw exception; nested exception is java.lang.NullPointerException

---

For example, bean that needs BaseConfigurationService:

    public class EmailNotificationService extends BaseService implements NotificationService {

        private BaseConfigurationService configurationService;

@Autowired
    public void setConfigurationService(BaseConfigurationService configurationService) {
        Assert.notNull(configurationService);
        this.configurationService = configurationService;
    }

    // the rest omitted... 
    }

---

#update 1

Bean initialization example with internal dependencies to another beans:

@Bean
    public TransactionDataService transactionDataService() {
        return new DefaultTransactionDataService();
    }

and DefaultTransactionDataService:

public class DefaultTransactionDataService implements TransactionDataService {
    private PrivateKeyService privateKeyService;

    @Autowired
    public void setPrivateKeyService(PrivateKeyService privateKeyService) {
        Assert.notNull(privateKeyService);
        this.privateKeyService = privateKeyService;
    }
}

and bean dependency

@Bean
    public PrivateKeyService privateKeyService() {
        return new DefaultPrivateKeyAwareService();
    }

and it works.

Answer 1

It is related to your instruction to Spring how to initialize your bean:

@Bean is used to explicitly declare a single bean, rather than letting Spring do it automatically as above. It decouples the declaration of the bean from the class definition, and lets you create and configure beans exactly how you choose.

So when you create instance of your class manually your have to set all class field manually as well.

It can be done like this:

@Bean
public BaseConfigurationService configurationService() {
    DefaultConfigurationService configurationService = new DefaultConfigurationService();
    configurationService.setTaxPayerService(taxPayerService());
    configurationService.initialize();
    return configurationService;
}

Or move dependency directly to constructor, so dependency of your DefaultConfigurationService will be more obvious:

@Bean
public BaseConfigurationService configurationService() {
    DefaultConfigurationService configurationService = new DefaultConfigurationService(taxPayerService());
    configurationService.initialize();
    return configurationService;
}

Good description