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Dependency Handler

The dependency handler manages OSGi service dependencies. It allows a component to consume service without managing service discovery, tracking and binding. The handler manages all this interaction and injects required service in the component.

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Dynamism & Instance Lifecycle

In OSGi™OSGi?, services can appear and disappear dynamically. This implies dependencies can target a service that can appear or disappear dynamically.  So, dependencies need to manage this dynamism by tracking every time available service. At any moment, a dependency can be unresolved.  In the case of a mandatory dependency, the instance becomes invalid (an invalid instance is no more accessible externally, for example provided service are unpublished). If a service, resolving the unfilled dependency appears, the instance becomes valid. In consequence, dependencies affect directly the instance state, and must manage correctly the dynamics of OSGi to allow a complete unloading when a service goes away. As soon a mandatory dependency cannot be fulfilled, the instance is invalidated.

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