RemoteServiceServlet with spring autowired gives nullpointerexception

Question

I'm using GWT with Spring. I encountered the problem of using an @Autowired bean in a RemoteServiceServlet. For some reason this doesn't work automatically and I need to use @Configurable to get this working. I followed this approach but I still get a NullPointerException for the @Autowired bean:

@Configurable
@Transactional(propagation = Propagation.REQUIRED, readOnly = false)
public class AServiceImpl extends RemoteServiceServlet implements AService {

    @Autowired
    private IABean aBean;

    @Override
    public void aMethodFromAService(Args arg[]) {
        aBean.aMethodOfABean(); // this gives a NullPointerException
    }
}

@Component
public class ABean implements IABean {
    ...
}

Any guidance in what is going on? Any extra information I need to provide?

where/how do you declare your ABean in Spring? XML or annotation? — spiritwalker, Feb 13 '13 at 12:29
do you have in application context file in order to make ABean a candidate for injection. — spiritwalker, Feb 13 '13 at 12:38
yes, and I used several @autowired before with success. It's the RemoteServiceServlet with GWT that causes the problem somehow — Vjeetje, Feb 13 '13 at 12:40
http://stackoverflow.com/questions/8933778/why-doesnt-just-autowiring-a-field-in-a-gwt-servlet-in-spring-work — Alexander, Feb 13 '13 at 12:44

score 0 · Accepted Answer · answered Feb 13 '13 at 12:54

0

http://mitosome.blogspot.be/2011/01/injecting-spring-beans-into-gwt.html

Thanks Alexander for putting me in the right direction

answered Feb 13 '13 at 12:54

Vjeetje

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score 0 · Answer 2 · answered Feb 13 '13 at 14:01

You found a workable solution, but just for the record and we have it working as follows:

public class MyServiceImpl extends RemoteServiceServlet 
                           implements MyService, ServletContextAware
{
    @Autowired private transient SomeService someService;
    ....
}

and

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

The SomeService is a completely vanilla XML-defined bean. Perhaps that or ...implements ServletContextAware makes a difference.

Cheers,

RemoteServiceServlet with spring autowired gives nullpointerexception

2 Answers2