EDIT

package eu.etaxonomy.cdm.persistence.dao.hibernate.statistics;

import org.hibernate.Criteria;

import org.hibernate.Query;

import org.hibernate.criterion.Projections;

import org.hibernate.criterion.Restrictions;

import org.springframework.stereotype.Repository;

import eu.etaxonomy.cdm.model.taxon.Classification;

import eu.etaxonomy.cdm.model.taxon.Synonym;

import eu.etaxonomy.cdm.model.taxon.Taxon;

import eu.etaxonomy.cdm.model.taxon.TaxonBase;

import eu.etaxonomy.cdm.model.taxon.TaxonNode;

import eu.etaxonomy.cdm.persistence.dao.hibernate.common.DaoBase;

import eu.etaxonomy.cdm.persistence.dao.statistics.IStatisticsDao;

@Repository

public class StatisticsDaoHibernateImpl extends DaoBase implements

		IStatisticsDao {

	/**

	 * @return be aware that the returned long might be null

	 */

	@Override

	public Long countNomenclaturalReferences() {

		return countNomenclaturalReferences("");

	}

	private Long countNomenclaturalReferences(String where) {

		Query query = getSession().createQuery(

				"select count(distinct nomenclaturalReference) from TaxonNameBase"

						+ where);

		return (Long) query.uniqueResult();

	}

	@Override

	public Long countNomenclaturalReferences(Class clazz) {

		return countNomenclaturalReferences("where" + clazz.getSimpleName());

	}

	/**

	 * @return be aware that the returned long might be null

	 */

	public Long countDescriptiveSourceReferences() {

		Query query;

		Long count = new Long(0);

		// count sources from Descriptions:

		query = getSession().createQuery(

				"select count(distinct d.descriptionSources) from DescriptionBase as d "

						+ "join d.descriptionSources");

		query = getSession()

				.createQuery(

						"select count(distinct s.citation) from DescriptionElementBase as d join d.sources as s");

		return (Long) query.uniqueResult();

	}

	// TODO remove this method:

	@Override

	public void tryArround() {

		Criteria criteria = getSession().createCriteria(Synonym.class);

		// Query query =

		// System.out.println("query: "+((Query) criteria).getQueryString());

		// System.out.println(getSession().createCriteria(Synonym.class);

		criteria.list();

		// criteria.

		// System.out.println(criteria.toString());

		System.out.println("");

	}

	@Override

	public Long countTaxaInClassification(Class<? extends TaxonBase> clazz,

			Classification classification) {

		if (clazz.equals(TaxonBase.class)) {

			return countTaxaInClassification(Taxon.class, classification)

					+ countTaxaInClassification(Synonym.class, classification);

		}

		if (clazz.equals(Taxon.class)) {

			Criteria criteria = getSession().createCriteria(TaxonNode.class);

			criteria = getSession().createCriteria(TaxonNode.class);

			criteria.add(Restrictions.eq("classification", classification));

			criteria.setProjection(Projections.rowCount());

			return Long.valueOf((Integer) criteria.uniqueResult());

			// Long counter = Long.valueOf((Integer) criteria.uniqueResult());

			// return counter;

		}

		else if (clazz.equals(Synonym.class)) {

			// criteria= getSession().createCriteria(TaxonNode.class);

			Query query = getSession().createQuery(

					"select count(distinct sr.relatedFrom.uuid) from TaxonNode tn "

							+ "join tn.taxon.synonymRelations as sr "

							+ "where tn.classification=:classification");

			query.setParameter("classification", classification);

			Long counter = (Long) query.uniqueResult();

			return counter;

			// return (Long) query.uniqueResult();

		}

		// this should never happen:

		return null;

	}

	@Override

	public Long countTaxonNames(Classification classification) {

		// TODO: merge the 2 queries below - you can't just add them because

		// there might be doubles

		Query query;

		// this is only the taxon names:

		// query = getSession().createQuery(

		// "select count(distinct tn.taxon.name) from TaxonNode tn "

		// + "where tn.classification=:classification");

		// this is only the synonym names:

		query = getSession().createQuery(

				"select count(distinct s.name) from TaxonNode tn "

						+ "join tn.taxon.synonymRelations sr "

						+ "join sr.relatedFrom s "

						+ "where tn.classification=:classification");

		// everything???:

		query = getSession()

				.createQuery(

						"select count(distinct s2) from TaxonNode tn " +

						"join tn.taxon.synonymRelations sr join sr.relatedFrom.name s1 " +

						"join tn.taxon.name s2 " +

						"where tn.classification=:classification");

		query.setParameter("classification", classification);

		return (Long) query.uniqueResult();

	}

}