code: @Reference(cardinality=ReferenceCardinality.MULTIPLE, policy=ReferencePolicy.DYNAMIC)
  	public void addFactory(FileSetProvider factory) {
  		if (logger.isLoggable(Level.FINER)) {
  			logger.finer("Adding factory: " + factory);
  		}
  		filters.add(factory);
  	}
docs: Adds a factory (intended for use by the OSGi framework)
  @param factory the factory to add