How to @autowire some bean into JsonSerializer?

Question

I am using lazy loading with hibernate in my web app.

I would like to load some objects from the database at the parsing stage of the server response

@Component
public class DesignSerializer extends JsonSerializer<Design> {
@Autowired
IDesignService designService; <-- is null

}

Which is totally understandable because DesignSerializer is being instantiated with the "new" operator for each object.

I am sure there is a way to inject my bean into that serializer when ever it is created, I just don't know how.

Can you guys help me or point me in the right direction.

If DesignSerializer is mark with @Component, it's suppose to be a bean if I'm not mistaken. You could grab the bean that was created by spring? — Marc-Andre, Jul 10 '13 at 16:36
how?, this serializer is being called by spring after finishing the controller with @ResponseBody — Gleeb, Jul 10 '13 at 16:43
don't you have an [Application Context](http://static.springsource.org/spring/docs/3.0.x/api/org/springframework/context/ApplicationContext.html) that you use getBean on it? — Marc-Andre, Jul 10 '13 at 16:44
If Spring isn't managing this bean, then it can't inject anything into it. — Sotirios Delimanolis, Jul 10 '13 at 17:51

score 30 · Accepted Answer · answered Feb 04 '14 at 20:41

30

Solution is SpringBeanAutowiringSupport if you are using Spring Framework 2.5+.

public class DesignSerializer extends JsonSerializer<Design> {

    @Autowired
        IDesignService designService;
    }

    public DesignSerializer(){
        SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this);    
    }

...

}

I Hope that help you

answered Feb 04 '14 at 20:41

Peter Jurkovic

2,455
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2

Awesome. So simple compared to other suggestions all over the Web. – Elnur Abdurrakhimov Feb 11 '14 at 22:12
+1 for SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this); It solve my problem too. – YROjha May 02 '14 at 11:17
can you please tell me how to use the autowire in my case with jackson? http://stackoverflow.com/questions/35436279/autowire-in-deserialization-class – secret Feb 17 '16 at 09:34
Does it work if you use a specific bean with @Qualifier? – Josseline Perdomo May 21 '19 at 14:22
@JosselinePerdomo Yes, it does – Peter Jurkovic Aug 27 '19 at 13:33

veiset · Answer 2 · 2014-07-03T11:38:38.880

We had the same problem with JsonSerializer and Spring autowiring. The solution that worked for us was to make two constructors. One for Spring which sets the dependency as a static field, and another one that is used by the Jackson initialisation.

This works because the Spring dependency injection (autowiring) happens before Jackson initialises the serializer.

@Component
public class MyCustomSerializer extends JsonSerializer<String> {

    private static IDesignService designService;

    // Required by Jackson annotation to instantiate the serializer
    public MyCustomSerializer() { }

    @Autowired
    public MyCustomSerializer(IDesignService designService) {
        this.designService = designService;
    }

    @Override
    public void serialize(String m, JsonGenerator gen, SerializerProvider s) {
        gen.writeObject(MyCustomSerializer.designService.method(..));
    }
}

Somehow I dont like the solution but I don't know how to do it on a better way. So I follow this way :-) — Michael Hegner, Nov 18 '19 at 13:51

score 4 · Answer 3 · edited May 23 '17 at 12:09

I Solved the problem by creating a static field in a different bean and then @Autowire its setter method.

@Service("ToolBox")
@Transactional
public class ToolBox 
{
static Logger logger = Logger.getLogger(ToolBox.class);


private static IService service;


@Autowired
public void setService(IService service)
{
    ToolBox.service = service;
}

public static IService getService()
{
    return ToolBox.service;
}}

like shown in this thread: Can you use @Autowired with static fields?

How to @autowire some bean into JsonSerializer?

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