CODEWITHSUNDEEP
javaspringvaadin
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Reputation: 5377

Vaadin constructor with Autowired Spring JPA beans

I have a Spring Boot application

@SpringBootApplication
public class TaxApplication {

  private static final Logger log = LoggerFactory.getLogger(TaxApplication.class);

  public static void main(String[] args) {
    SpringApplication.run(TaxApplication.class, args);
  }
}

I've set it up with Spring JPA for data access

spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
spring.jpa.hibernate.ddl-auto=none
spring.jpa.hibernate.show-sql=true

I've set up a JPA Repository for the Account table:

public interface AccountRepository extends JpaRepository<Account, Long> {

    List<Account> findByNameStartsWithIgnoreCase(String name);
}

In my MainView, the AccountRepository doesn't get @Autowired by the Spring framework,

I can get an instance of it by Constructor injection:

public MainView(AccountRepository accountRepository) {
}

BUT If I try to use Autowiring the Constructor outputs 'null'

@Route
@Configurable
@PageTitle("Basic App Layout")
@CssImport(value = "combobox-styles.css", themeFor="vaadin-combo-box-overlay")
public class MainView extends AppLayout {
    
    @Autowired
    AccountRepository accountRepository;
    
    public MainView() {
        
        System.out.println(accountRepository);
    }
}

Is this because the code is called from the MainView Constructor? How can we use Autowired JPA beans with Vaadin?

EDIT: I have added @EnableJpaRepositories to the Application, but Autowiring still fails

@SpringBootApplication
@EnableJpaRepositories(basePackages= {"org.mypackage.tax.repo"})
public class TaxApplication {

Upvotes: 0

Views: 508

Answers (3)

Erik Lumme
Erik Lumme

Reputation: 5352

That's just how autowiring in Spring works.

When you're using constructor injection, you can leave out the @Autowired annotation as long as there's just one constructor, but it's still autowired.

When you're using fields or setters, the dependencies will be injected after the bean has been constructed. This is unrelated to Vaadin.

Constructor injection is generally preferred over field injection. It makes the class easier to test, since you can easily pass mocks or stubs to the constructor when you instantiate it yourself.

Upvotes: 4

Abdennacer Lachiheb
Abdennacer Lachiheb

Reputation: 4888

add this to your application TaxApplication:

@EnableJpaRepositories(basePackages= {"com.tax.persistence"})

com.tax.persistence is the package that contains your repositories.

Also you can annotate MainView with @Component to make it Spring bean.

Upvotes: 0

Donato Amasa
Donato Amasa

Reputation: 856

You can try and add @EnableJpaRepositories annotation to your TaxApplication class

Upvotes: 0

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