ReaderFacade.java

package fi.insomnia.bortal.facade;

import java.util.List;

import javax.ejb.EJB;
import javax.ejb.LocalBean;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.TypedQuery;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

import fi.insomnia.bortal.beans.EventBeanLocal;
import fi.insomnia.bortal.model.LanEvent;
import fi.insomnia.bortal.model.Reader;
import fi.insomnia.bortal.model.Reader_;

@Stateless
@LocalBean
public class ReaderFacade extends GenericFacade<Integer, Reader> {

	@PersistenceContext
	private EntityManager em;

	@EJB
	private EventBeanLocal eventbean;

	public ReaderFacade() {
		super(Reader.class);
	}

	@Override
	protected EntityManager getEm() {
		return em;
	}

	public Reader findByIdent(LanEvent event, String reader) {
		CriteriaBuilder cb = getEm().getCriteriaBuilder();
		CriteriaQuery<Reader> cq = cb.createQuery(Reader.class);
		Root<Reader> root = cq.from(Reader.class);

		cq.select(root);
		TypedQuery<Reader> q = getEm().createQuery(cq);
		cq.where(
				cb.and(
						cb.equal(root.get(Reader_.event), event),
						cb.equal(root.get(Reader_.identification), reader)));

		return getSingleNullableResult(q);
	}

	public Reader findOrCreateByIdent(String ident) {
		LanEvent event = eventbean.getCurrentEvent();
		Reader ret = findByIdent(event, ident);
		if (ret == null) {
			ret = createIdent(this, event, ident);
		}
		return ret;
	}

	private static synchronized Reader createIdent(ReaderFacade rf, LanEvent ev, String ident) {
		Reader ret = rf.findByIdent(ev, ident);
		if (ret == null) {
			ret = new Reader(ev, ident);
			ret.setDescription("Automagically created");
			rf.create(ret);
		}
		return ret;
	}

	public List<Reader> findAllForEvent() {
		CriteriaBuilder cb = getEm().getCriteriaBuilder();
		CriteriaQuery<Reader> cq = cb.createQuery(Reader.class);
		Root<Reader> root = cq.from(Reader.class);
		cq.where(cb.equal(root.get(Reader_.event), eventbean.getCurrentEvent()));
		return em.createQuery(cq).getResultList();
	}
}