if (vigilant.hasIncompatiblePerson()) {
Person incompatiblePerson = vigilant.getIncompatiblePerson(); if (incompatiblePerson != null && !vigilants.contains(incompatiblePerson.getCurrentVigilant())) {
    public List<Vigilant> getVigilantsWithIncompatiblePerson() {        List<Vigilant> vigilants = new ArrayList<Vigilant>();        for (Vigilant vigilant : this.getVigilants()) {            if (vigilant.hasIncompatiblePerson()) {                vigilants.add(vigilant);            }        }        return vigilants;    }