Is there a simpler method for handling MULTIPLE references in OSGi?

Question

Suppose I have a class like this:

@References(
        value={
                @Reference(name="dataSources",cardinality=ReferenceCardinality.OPTIONAL_MULTIPLE,policy=ReferencePolicy.DYNAMIC,strategy=ReferenceStrategy.EVENT,bind="bind",unbind="unbind",referenceInterface=DataSourceProvider.class)
        })      
public class DataSourceStoreServiceImpl implements DataSourceStoreService {

    List<DataSourceProvider> dataSourceProviders = new CopyOnWriteArrayList<DataSourceProvider>();

    public void bind(DataSourceProvider dataSourceProvider) {
        dataSourceProviders.add(dataSourceProvider);
    }

    public void unbind(DataSourceProvider dataSourceProvider) {
        dataSourceProviders.remove(dataSourceProvider);
    }

}

This is how I handle refereces with MULTIPLE cardinality.

My question is whether it is possible to do it without the boilerplate? What I have in mind is something like this:

public class DataSourceStoreServiceImpl implements DataSourceStoreService {

    @CollectionType(CopyOnWriteArrayList.class)
    @Reference(name="dataSources",cardinality=ReferenceCardinality.OPTIONAL_MULTIPLE,policy=ReferencePolicy.DYNAMIC,strategy=ReferenceStrategy.EVENT,bind="bind",unbind="unbind",referenceInterface=DataSourceProvider.class)
    List<DataSourceProvider> dataSourceProviders

}

If you are using felix, have you tried iPOJO as this is designed to make these issues much simpler to deal with. — Peter Lawrey, Apr 23 '14 at 14:12
You should find iPOJO *much* simpler to use. (or at least that is it's purpose AFAIK) I have used it in a number of projects, but never tried to use Felix by itself. — Peter Lawrey, Apr 23 '14 at 15:06
I'm actually using Karaf (which uses Felix). Does it work with Karaf? — Adam Arold, Apr 23 '14 at 15:07
I have only used iPOJO and Karaf, actually. ;) They work together very well. IMHO. — Peter Lawrey, Apr 23 '14 at 15:08

score 0 · Accepted Answer · edited Apr 23 '14 at 16:46

Using IPojo annotations.

Simply declaring an array with the annotation "requires" as in this example:

@Requires
private Hello[] m_hello; // Service Dependency

Then you can call your services like that:

for(Hello helloService: m_hello){
       helloService.ohHai("Test");
}

Oh I forgot, your provider class needs 2 annotations: @Component and @Provides and your consumer class needs @Component and @Instantiate

Is there a simpler method for handling MULTIPLE references in OSGi?

1 Answers1