import java.util.Collection;
import java.util.Collections;
-
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;
+import org.osgi.util.tracker.ServiceTracker;
+import org.osgi.util.tracker.ServiceTrackerCustomizer;
+
+public abstract class AbstractConsumer implements Consumer, BundleActivator,ServiceTrackerCustomizer<Broker, Broker> {
-public abstract class AbstractConsumer implements Consumer, BundleActivator {
+ private BundleContext context;
+ private ServiceTracker<Broker, Broker> tracker;
+ private Broker broker;
- Broker broker;
- ServiceReference<Broker> brokerRef;
@Override
- public final void start(BundleContext context) throws Exception {
- this.startImpl(context);
- brokerRef = context.getServiceReference(Broker.class);
- broker = context.getService(brokerRef);
- broker.registerConsumer(this,context);
+ public final void start(final BundleContext bundleContext) throws Exception {
+ this.context = bundleContext;
+ this.startImpl(bundleContext);
+ tracker = new ServiceTracker<>(bundleContext, Broker.class, this);
+ tracker.open();
}
-
-
@Override
- public final void stop(BundleContext context) throws Exception {
- stopImpl(context);
+ public final void stop(final BundleContext bundleContext) throws Exception {
+ stopImpl(bundleContext);
broker = null;
- if(brokerRef != null) {
- context.ungetService(brokerRef);
+
+ if (tracker != null) {
+ tracker.close();
}
}
- protected void startImpl(BundleContext context) {
+ protected void startImpl(final BundleContext bundleContext) {
// NOOP
}
- protected void stopImpl(BundleContext context) {
+
+ protected void stopImpl(final BundleContext bundleContext) {
// NOOP
}
return Collections.emptySet();
}
+
+ @Override
+ public Broker addingService(final ServiceReference<Broker> reference) {
+ if (broker == null && context != null) {
+ broker = context.getService(reference);
+ broker.registerConsumer(this, context);
+ return broker;
+ }
+
+ return null;
+ }
+
+ @Override
+ public void modifiedService(final ServiceReference<Broker> reference, final Broker service) {
+ // NOOP
+ }
+
+ @Override
+ public void removedService(final ServiceReference<Broker> reference, final Broker service) {
+ stopImpl(context);
+ }
}