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Dependency Manager - Bundle Dependency

A bundle dependency allows you to depend on a bundle in a certain set of states, as indicated by a state mask. You can also use a filter condition that is matched against all manifest entries. Finally you can provide a reference to an existing bundle.

To define a bundle dependency, you need to use the BundleDependecy interface. This interface can be created using DependencyActivatorBase.createBundleDependency() or DependencyManager.createBundleDependency() methods;

Here is an example of a component which tracks all ACTIVE bundles having a Service-Component header in the manifest:

public class Activator extends DependencyActivatorBase {
    @Override
    public void init(BundleContext ctx, DependencyManager dm) throws Exception {
        Component scr = createComponent()
                .setImplementation(ScrRuntime.class)
                .add(createBundleDependency().setFilter("(Service-Component=*").setStateMask(Bundle.ACTIVE).setCallbacks("bind", "unbind"));
    }
}

public class ScrRuntime {
    void bind(Bundle bundle) {
        // load SCR descriptors from the starting bundle
    }

    void unbind(Bundle bundle) {
        // unload SCR descriptors from the starting bundle
    }
}

The dependency is optional by default, and will invoke the ScrRuntime.bind callback each time a bundle containing some Declarative Service component is started.

Rev. 1844582 by pderop on Mon, 22 Oct 2018 17:10:53 +0000
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