aa.PersonDog.dao.AbstractDao.java Source code

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Here is the source code for aa.PersonDog.dao.AbstractDao.java

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/*
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http://www.java2s.com/Code/Java/Hibernate/GenericDaoCreate.htm
    
 */
package aa.PersonDog.dao;

import java.io.Serializable;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;

import java.util.List;
import java.util.Map;
import org.hibernate.Criteria;
import org.hibernate.criterion.Example;
import org.hibernate.criterion.MatchMode;

public abstract class AbstractDao implements Serializable {

    private Session session;
    private Transaction tx = null;

    public AbstractDao() {
        HibernateFactory.buildIfNeeded();
    }

    protected void save(Object obj) {
        try {
            startOperation();
            session.save(obj);
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected void update(Object obj) {
        try {
            startOperation();
            session.update(obj);
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected void saveOrUpdate(Object obj) {
        try {
            startOperation();
            session.saveOrUpdate(obj);
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected void delete(Object obj) {
        try {
            startOperation();
            session.delete(obj);
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected Object find(Class clazz, Long id) {
        Object obj = null;
        try {
            startOperation();
            obj = session.load(clazz, id);
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return obj;
    }

    protected List queryByExample(Object obj) {

        List objects = null;

        try {
            startOperation();

            // https://docs.jboss.org/hibernate/orm/3.3/reference/en/html/querycriteria.html  
            // http://blog.caelum.com.br/simplifique-suas-consultas-com-o-query-by-example-do-hibernate/

            Example ex = Example.create(obj).excludeZeroes() //exclude zero valued properties
                    .ignoreCase() //perform case insensitive string comparisons
                    .enableLike(MatchMode.ANYWHERE); //use like for string comparisons
            Criteria criteria = session.createCriteria(obj.getClass()).add(ex);
            objects = criteria.list();

            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return objects;
    }

    protected List findAll(Class clazz) {
        List objects = null;
        try {
            startOperation();
            Query query = session.createQuery("from " + clazz.getName());
            objects = query.list();
            commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return objects;
    }

    protected Class findOneResult(String namedQuery, Map<String, Object> parameters) {

        return null;

    }

    protected void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }

    protected void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }

    protected void commit() throws HibernateException {
        if (tx != null) {
            tx.commit();
            tx = null;
        }
    }

    protected void endOperation() throws HibernateException {
        HibernateFactory.close(session);
    }
}