if (role == null) return false;
    public final boolean acceptsParticipationRole(ResultParticipationRole role) {        if (this instanceof Proceedings) {            if (role.equals(ResultParticipationRole.Editor)) {                return true;            }        }        if (this instanceof Book || this instanceof BookPart || this instanceof Inproceedings) {            if (role.equals(ResultParticipationRole.Editor)                    || role.equals(ResultParticipationRole.Author)) {                return true;            }        }        if (role.equals(ResultParticipationRole.Author)) {            return true;        }        return false;    }