The OSGi Alliance has developed a specification describing integration between OSGi and CDI. The combination of these two powerful development technologies opens the door to new possibilities. This talk will walk through the most essential features of the specification and show some code and running examples.

1.
OSGi CDI Integration Specification
Raymond Augé - Sr. So ware Architect
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2. Why CDI In OSGi?
Important Java specification
Reduce developer friction
Benefit from extensive feature set
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3. CDI - Features
as part of its feature set, is...
extensible (CDI has a full fledged SPI)
annotation processing engine
intra-bundle dependency injection
Custom annotations!
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4. CDI - Internal wiring: @Inject
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import javax.inject.Inject;
public class PresenterImpl implements Presenter {
private final Laptop laptop;
@Inject
public PresenterImpl(Laptop laptop) {
this.laptop = laptop;
}
}
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5. CDI - Internal wiring: @Produces
@rotty3000
import javax.enterprise.inject.Produces;
@Produces Presentation presentation(
LocalDate date, Presenter presenter, @Topic String
topic,
Details details) {
return new Presentation.Builder(date)
.withPresenter(presenter)
.withTopic(topic)
.withDetails(details)
.build();
}
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6. OSGi-CDI - Services: singleton
@rotty3000
import org.osgi.service.cdi.annotations.Service;
@Service
public class PresenterImpl implements Presenter {
...
}
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7. OSGi-CDI - Services: prototype
@rotty3000
import org.osgi.service.cdi.annotations.Service;
import org.osgi.service.cdi.annotations.ServiceInstance;
@Service @ServiceInstance(PROTOTYPE)
public class Beer implements Drink {
...
}
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8. OSGi-CDI - References to OSGi Services
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Presenter presenter;
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9. OSGi-CDI - References Cardinality: mandatory
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Presenter presenter;
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10. OSGi-CDI - References Cardinality: optional
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Optional<Drink> drink;
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11. OSGi-CDI - References Cardinality: multiple
... implies 0..n (multiple optional)
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
List<Drink> drink;
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12. OSGi-CDI - References Cardinality: at least one
(or n)
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.MinimumCardinality;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference @MinimumCardinality(1)
List<Drink> drink;
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13. OSGi-CDI - Reference Policy: reluctant
... reference is Greedy by default
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
import org.osgi.service.cdi.annotations.Reluctant;
@Inject @Reference @Reluctant
Presenter presenter;
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14. OSGi-CDI - References Dynamic: mandatory
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Provider<Presenter> presenter;
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15. OSGi-CDI - References Dynamic: multiple
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Provider<List<Presenter>> presenters;
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16. OSGi-CDI - References Dynamic: optional
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference
Provider<Optional<Presenter>> presenter;
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17. OSGi-CDI - Reference: target
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference(target = "(service.vendor=Chicago JUG)")
List<Presenter> presenters;
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18. OSGi-CDI - Reference: target
@BeanPropertyType
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
import org.osgi.service.cdi.propertytypes.ServiceVendor;
@Inject @Reference @ServiceVendor("Chicago JUG")
List<Presenter> presenters;
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19. OSGi-CDI - Reference: prototype required
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.MinimumCardinality;
import org.osgi.service.cdi.annotations.PrototypeRequired;
import org.osgi.service.cdi.annotations.Reference;
@Inject @Reference @MinimumCardinality(1)
@PrototypeRequired
List<Entry<Map<String, Object>, Drink>> drinks;
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20. OSGi-CDI - Reference: any type
... in support of whiteboards
@rotty3000
import javax.inject.Inject;
import org.osgi.service.cdi.annotations.Reference;
import org.osgi.service.cdi.propertytypes.ServiceVendor;
@Inject @Reference(service = Reference.Any.class)
@ServiceVendor("Chicago JUG")
List<Object> all;
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21. OSGi-CDI - Reference: service events
@rotty3000
import javax.inject.Inject;
@Inject @ServiceVendor("Chicago JUG")
void monitorDrinks(BindServiceReference<Drink> drinks) {
drinks
.adding(this::doAdd)
.modified(this::doModified)
.removed(this::doRemoved)
.bind();
}
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22. OSGi-CDI - OSGi Logger
@rotty3000
import javax.inject.Inject;
import org.osgi.service.log.Logger;
@Inject
Logger video;
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23. OSGi-CDI - Configuration
@rotty3000
import javax.inject.Inject;
import
org.osgi.service.cdi.annotations.ComponentProperties;
@Inject @ComponentProperties
Map<String, Object> eventDetails;
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24. OSGi-CDI - Configuration Types
@rotty3000
import org.osgi.service.cdi.annotations.BeanPropertyType;
@Retention(RUNTIME)
@BeanPropertyType
public @interface Details {
String address();
String instructions();
}
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25. OSGi-CDI - Configuration: typed
@rotty3000
import javax.inject.Inject;
import
org.osgi.service.cdi.annotations.ComponentProperties;
@Inject @ComponentProperties
Details eventDetails;
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26. OSGi-CDI - Single Component
@rotty3000
import org.osgi.service.cdi.annotations.PID;
import org.osgi.service.cdi.annotations.SingleComponent;
@SingleComponent
@PID(value = "details", policy = REQUIRED)
@Service
public PresenterImpl implements Presenter {
@Inject Laptop laptop;
@Inject @ComponentProperties Details eventDetails;
}
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27. OSGi-CDI - Factory Component
@rotty3000
import org.osgi.service.cdi.annotations.PID;
import org.osgi.service.cdi.annotations.FactoryComponent;
@FactoryComponent("registration")
@PID(value = "details", policy = REQUIRED)
public class AttendeeImpl implements Attendee {
@Inject @ComponentProperties Registration registration;
@Inject @ComponentProperties Details eventDetails;
}
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28. The OSGi-CDI Spec
https://osgi.org/specification/osgi.enterprise/7.0.0/service.cdi.html
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29. The OSGi-CDI Reference Implementation
https://github.com/apache/aries-cdi
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