public void write(final Flugplan flugplan, final ConfluenceUser user) {
	String flugplanJson = flugplanConverter.toJson(flugplan);
	UserFlugplanRelation[] userFlugplanRelations = ao.find(UserFlugplanRelation.class, "USER_KEY = ?", (us-er.getKey().getStringValue()));

	if (userFlugplanRelations[0] != null) {
		log.debug("flugplan already exists");
		removeRelation(userFlugplanRelations[0]);
	}
	log.debug("flugplan is new");
	ao.create(UserFlugplanRelation.class, new DBParam("USER_KEY", us-er.getKey().getStringValue()), new DBParam("FLUGPLAN", flugplanJson));
}