How to inject ApplicationContext itself

Question

I want to inject an ApplicationContext itself to a bean.

Something like

public void setApplicationContext(ApplicationContect context) {
  this.context = context;
}

Is that possible in spring?

score 142 · Accepted Answer · answered Feb 07 '11 at 01:33

142

Previous comments are ok, but I usually prefer:

@Autowired private ApplicationContext applicationContext;

answered Feb 07 '11 at 01:33

sinuhepop

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4

+1 Btw, do you have any idea about pros cons between injecting applicationContext by directly @Autowired or implementing ApplicationContextAware interface? Thanks. – javatar Mar 11 '12 at 18:58
9

@Bariscan: I think there are no pros and cons. But I prefer this because @ Autowired is what I use for injecting all properties, so whay to do it differently just beacuse is an ApplicationContext? – sinuhepop Mar 11 '12 at 23:02
1

Can you provide a more detailed example of @Autowired (I'm a big fan) Application context? It is always null for me. Any extra interfaces needed? Thx. – Joseph Lust Mar 26 '12 at 21:53
Is @Autowired injecting other properties in same bean? The exact same code works for me in Spring 3.1.1. – sinuhepop Mar 27 '12 at 08:20
4

While I agree that `@Autowired` is nice; The difference between using `@Autowired` and ApplicationContextAware can be astonishing when circular references are involved. It turned out that simply removing `@Autowired` solved the issue I described in [circular-dependency-in-spring](http://stackoverflow.com/questions/3485347/circular-dependency-in-spring/17111644#17111644) – jontejj Jun 17 '13 at 10:54

score 44 · Answer 2 · edited Mar 11 '14 at 10:35

44

Easy, using the ApplicationContextAware interface.

public class A implements ApplicationContextAware {
  private ApplicationContext context;

  public void setApplicationContext(ApplicationContext context) {
      this.context = context;
  }
}

Then in your actual applicationContext you only need to reference your bean.

<bean id="a" class="com.company.A" />

edited Mar 11 '14 at 10:35

Sergii Shevchyk

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answered Feb 06 '11 at 14:57

Johan Sjöberg

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score 13 · Answer 3 · answered Feb 06 '11 at 14:58

13

Yes, just implement the ApplicationContextAware -interface.

answered Feb 06 '11 at 14:58

esaj

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user2587779 · Answer 4 · 2020-05-08T17:44:39.083

I saw some comments above about @Autowired not working still. The following may help.

This will not work:

@Route(value = "content", layout = MainView.class)
public class MyLayout extends VerticalLayout implements RouterLayout {

  @Autowired private ApplicationContext context;

   public MyLayout() {
    comps.add(context.getBean(MyComponentA.class)); // context always null :(
}

You must do this:

 @Autowired
  public MyLayout(ApplicationContext context) {
    comps.add(context.getBean(MyComponentA.class)); //context is set :)
}

or this:


@PostConstruct
    private void init() {
    comps.add(context.getBean(MyComponentA.class)); // context is set :)
}

Also note that Upload is another component that must be set within the scope of @PostConstruct. This was a nightmare for me to figure out. Hope this helps!

I almost forgot to mention that the @Scope annotation may be necessary for your Bean, as seen below. This was the case when using Upload within a Bean because the UI is not instantiate/attached prior to the Bean being created and will cause a Null Reference Exception to be thrown. It won't do so when using @Route, but will when using @Component - so the latter is not an option and if @Route is not viable, then I would recommend using @Configuration class to create the bean with the prototype scope.

@Configuration
public class MyConfig {
  @Bean
  @Scope(value = ConfigurableBeanFactory.SCOPE_PROTOTYPE, proxyMode = ScopedProxyMode.TARGET_CLASS)
  public MyComponentA getMyBean() {
    return new MyComponentA();
  }
}

Grigory Kislin · Answer 5 · 2021-10-02T13:44:16.770

2

Special solution: get Spring beans from any (non Spring) classes

@Component
public class SpringContext {
    private static ApplicationContext applicationContext;

    @Autowired
    private void setApplicationContext(ApplicationContext ctx) {
        applicationContext = ctx;
    }

    public static <T> T getBean(Class<T> componentClass) {
        return applicationContext.getBean(componentClass);
    }
}

edited Oct 02 '21 at 13:44

answered Feb 25 '21 at 09:32

Grigory Kislin

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How to inject ApplicationContext itself

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