code: @Override
  	public void shutdown(IAggregator aggregator) {
  		for (IServiceRegistration reg : serviceRegs) {
  			reg.unregister();
  		}
  		serviceRegs.clear();
  	}
docs: /* (non-Javadoc)
  @see com.ibm.jaggr.service.IShutdownListener#shutdown(com.ibm.jaggr.service.IAggregator)