Question

I have 2 components A and B. A depends on B. I wrote something like:

public class A {
    private B b;
    @Autowired
    public void setB(B b) {
        this.b = b;
    }
}

@Component
public class B {}

new XmlBeanFactory(new FileSystemResource("./spring.xml")).getBean(A.class);

config

<context:annotation-config/>
<context:component-scan
    base-package="com">
</context:component-scan>

<bean class="com.A" autowire="byType" />

It worked perfectly well. Now I want configure A by annotations too. So I add @Component annotation to A

@Component
public class A {
    private B b;
    @Autowired
    public void setB(B b) {
        this.b = b;
    }
}

And removed A description from configuration. So it just

<context:annotation-config/>
<context:component-scan
    base-package="com">
</context:component-scan>

But B doesn’t injected anymore. Probably I should specify autowiring type or smt like that. So how I can fix it?

Answer 1

You have to use ApplicationContext instead of plain BeanFactory. Seems like BeanFactory does not run post processors, including the one looking for @Autowired annotation. I will try to find a piece of documentation for that, in the meantime try:

new ClassPathXmlApplicationContext("/spring.xml").getBean(B.class);

BTW @Autowired is completely valid on setters, constructors, fields, etc. (source):

Marks a constructor, field, setter method or config method as to be autowired by Spring’s dependency injection facilities.