public Collection getAvailableGateways(List allGateways) { Set gateways = new HashSet(allGateways); Collection ruleGateways = getGateways();
public Collection<Gateway> getAvailableGateways(List<Gateway> allGateways) { Set<Gateway> gateways = new HashSet<Gateway>(allGateways); Collection<Gateway> ruleGateways = getGateways();
    public Collection getAvailableGateways(List allGateways) {        Set gateways = new HashSet(allGateways);        Collection ruleGateways = getGateways();        gateways.removeAll(ruleGateways);        return gateways;    }