Is context:annotation-config an alternative to @AutoWired?

Question

Is it correct that I can put context:annotation-config in my XML config and it will automatically inject the bean class without needing any annotations?

So instead of using these annotation types:

public class Mailman
{
    private String name;

    @Autowired
    private Parcel Parcel;

    public Mailman(String name)
    {
        this.name = name;
    }

    @Autowired
    public void setParcel(Parcel Parcel)
    {
        this.Parcel = Parcel;
    }

    @Autowired
    public void directionsToParcel(Parcel Parcel)
    {
        this.Parcel = Parcel;
    }

}

I would just need to write this:

<beans ... >
<bean id="mailMan" class="MailMan">
 <constructor-arg value="John Doe"/>
</bean>
<bean id="parcel" class="Parcel" />
<context:annotation-config />
</beans>

and then my MailMan class would look a lot simpler without the need for annotations:

public class Mailman
{
    private String name;

    private Parcel Parcel;

    public Mailman(String name)
    {
        this.name = name;
    }    
}

Answer 1

<context:annotation-config /> just auto-registers all the standard bean post processors provided by Spring like PersistenceAnnotationBeanPostProcessor, AutowiredAnnotationBeanPostProcessor, CommonAnnotationBeanPostProcessor and RequiredAnnotationBeanPostProcessor, so that you don't have to register them individually in your spring context file. You still have to provide the @Autowired annotations on the attributes/setter as earlier.

Answer 2

No.

@Autowired Annotations are needed on the class along with <context:annotation-config/>

The xml config part is not needed when using the annotations.

Also from the doc Note that <context:annotation-config/> only looks for annotations on beans in the same application context it is defined in. This means that, if you put in a WebApplicationContext for a DispatcherServlet, it only checks for @Autowired beans in your controllers, and not your services.

If you dont need to use annotations then you need to specify the xml configuration.

Answer 3

By default, a Spring context will pay no attention to @Autowired annotations. In order to process them, the context needs to have a AutowiredAnnotationBeanPostProcessor bean registered in the context.

<context:annotation-config/> registers one of these for you (along with a few others), so you do need it (unless you register AutowiredAnnotationBeanPostProcessor yourself, which is perfectly valid).

If you don't like having @Autowired in your code, then you can explicitly inject properties in the XML using <property>, which just moves the clutter from one place to another.

If your context is extremely simple, then you can use implicit autowiring, as described here. Essentially, this tells Spring to autowire automatically by property name or type. This required very little configuration, but it very quickly gets out of control - it's automatic nature means it's hard to control, and gives you very little flexibility.

@Autowired really is the best option, in general.