if (filterstring != null) filter = new FilterImpl(filterstring);
if (filterstring == null) { this.filter = null; this.objectClass = null; } else { FilterImpl filterImpl = new FilterImpl(filterstring); String clazz = filterImpl.getRequiredObjectClass(); if (clazz == null) { this.objectClass = null; this.filter = filterImpl; } else { this.objectClass = clazz.intern();  String objectClassFilter = FilterImpl.getObjectClassFilterString(this.objectClass); this.filter = (objectClassFilter.equals(filterstring)) ? null : filterImpl; } }
	protected FilteredServiceListener(String filterstring, ServiceListener listener, BundleContextImpl context) throws InvalidSyntaxException {		if (filterstring != null)			filter = new FilterImpl(filterstring);		this.listener = listener;		this.context = context;		this.allservices = (listener instanceof AllServiceListener);	}