@Override
public void addTrend(String name, Kwet kwet) {
Query q = em.createQuery("select trend from Trends trend where trend.name = :name ");
q.setParameter("name", name);
List<Trend> trends = q.getResultList();
Trend trend = null;
if (trends.isEmpty()) {
trend = new Trend(name);
em.persist(trend);
trend.addKwet(kwet);
kwet.addTrend(trend);
em.merge(trend);
em.merge(kwet);
} else {
trend = trends.get(0);
if (!trend.getKwets().contains(kwet)) {
trend.addKwet(kwet);
kwet.addTrend(trend);
em.merge(trend);
em.merge(kwet);
}
}
}
