OSGI

Service implementation activator:

public void start(BundleContext bundleContext) throws Exception {
Activator.context = bundleContext;
SongHibernateDAO df = new SongHibernateDAO();
//NewImplementation df = new NewImplementation();
sr=(ServiceRegistration<SongDAO>) context.registerService(SongDAO.class.getName(), (Object)df, null);
}

Service interface activator:

public class Activator implements BundleActivator {

    public void start(BundleContext context) {

        System.out.println("Starting the bundle");

    }

    public void stop(BundleContext context) {

        System.out.println("Stopping the bundle");

    }

Service consumer activator:

 public void start(BundleContext bundleContext)
    {

    Activator.context = bundleContext;
ServiceReference reference = bundleContext.getServiceReference(SongDAO.class.getName());
//ServiceReference reference = bundleContext.getServiceReference(RandomQuoteService.class.getName());
if (reference == null) {
System.out.println("NULL");
} else {
// System.out.println("service found");
};

try {
service =  (SongDAO)context.getService(reference); //??
}catch(Exception ex) {
ex.printStackTrace();
}
MyServiceTrackerCustomizer customTracker = new MyServiceTrackerCustomizer(bundleContext);
serviceTracker = new ServiceTracker(bundleContext, SongDAO.class.getName(), customTracker);
serviceTracker.open();
    }

POM.XLS extra:

o  <Embed‐Transitive>True</Embed‐Transitive>

o  <Embed‐Dependency>*<Embed‐Dependency> 

o  <Import‐Package> org.osgi.framework,  *;resolution:=optional </Import‐Package>