StorageService.java

/**
 * This file is part of Faktotum.
 *
 *
 *  Faktotum is free software: you can redistribute it and/or 
 *  modify it under the terms of the GNU Lesser General Public License 
 *  as published by the Free Software Foundation, either version 3 of 
 *  the License, or (at your option) any later version.
 *
 *  Faktotum is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public 
 *  License along with Faktotum.  
 *
 *  If not, see <http://www.gnu.org/licenses/>.
 */
package de.romankreisel.faktotum.dao;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.criteria.CriteriaBuilder;

import de.romankreisel.faktotum.FaktotumObject;
import de.romankreisel.faktotum.datamodel.FaktotumEntity;

/**
 * The logic to persist and remove entities to/from the database.
 * 
 * @author Roman Kreisel <mail@romankreisel.de>
 */
@Stateless
public class StorageService extends FaktotumObject {
	@PersistenceContext(unitName = "Faktotum")
	private EntityManager entityManager;

	public CriteriaBuilder getCriteriaBuilder() {
		return this.getEntityManager().getCriteriaBuilder();
	}

	public EntityManager getEntityManager() {
		if (this.entityManager == null) {
			throw new NullPointerException("EntityManager not initialized!");
		}
		return this.entityManager;
	}

	/**
	 * Persists an entity
	 * 
	 * @param entity
	 *            the entity to be persisted
	 */
	public void persist(FaktotumEntity entity) {
		this.getEntityManager().persist(entity);
	}

	/**
	 * Removes an entity
	 * 
	 * @param entity
	 *            the entity to be removed
	 */
	public void remove(FaktotumEntity entity) {
		this.getEntityManager().remove(entity);
	}

	/**
	 * Normally the entity manager is injected, but this method can be used e.G.
	 * for JUnit tests.
	 * 
	 * @param entityManager
	 */
	public void setEntityManager(EntityManager entityManager) {
		this.entityManager = entityManager;
	}

}