questiondao.java

基于struts+hibernate的电子商务网站。可运行。数据库mysql

package tarena.dao;

import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.LockMode;
import org.hibernate.Query;
import org.hibernate.criterion.Example;

import tarena.entity.Question;

/**
 * Data access object (DAO) for domain model class Question.
 * 
 * @see tarena.entity.Question
 * @author MyEclipse Persistence Tools
 */

public class QuestionDAO extends BaseHibernateDAO {
	private static final Log log = LogFactory.getLog(QuestionDAO.class);

	// property constants
	public static final String QUESTION = "question";

	public void save(Question transientInstance) {
		log.debug("saving Question instance");
		try {
			getSession().save(transientInstance);
			log.debug("save successful");
		} catch (RuntimeException re) {
			log.error("save failed", re);
			throw re;
		}
	}

	public void delete(Question persistentInstance) {
		log.debug("deleting Question instance");
		try {
			getSession().delete(persistentInstance);
			log.debug("delete successful");
		} catch (RuntimeException re) {
			log.error("delete failed", re);
			throw re;
		}
	}

	public Question findById(java.lang.Integer id) {
		log.debug("getting Question instance with id: " + id);
		try {
			Question instance = (Question) getSession().get(
					"tarena.entity.Question", id);
			return instance;
		} catch (RuntimeException re) {
			log.error("get failed", re);
			throw re;
		}
	}

	public List findByExample(Question instance) {
		log.debug("finding Question instance by example");
		try {
			List results = getSession()
					.createCriteria("tarena.entity.Question").add(
							Example.create(instance)).list();
			log.debug("find by example successful, result size: "
					+ results.size());
			return results;
		} catch (RuntimeException re) {
			log.error("find by example failed", re);
			throw re;
		}
	}

	public List findByProperty(String propertyName, Object value) {
		log.debug("finding Question instance with property: " + propertyName
				+ ", value: " + value);
		try {
			String queryString = "from Question as model where model."
					+ propertyName + "= ?";
			Query queryObject = getSession().createQuery(queryString);
			queryObject.setParameter(0, value);
			return queryObject.list();
		} catch (RuntimeException re) {
			log.error("find by property name failed", re);
			throw re;
		}
	}

	public List findByQuestion(Object question) {
		return findByProperty(QUESTION, question);
	}

	public List findAll() {
		log.debug("finding all Question instances");
		try {
			String queryString = "from Question";
			Query queryObject = getSession().createQuery(queryString);
			return queryObject.list();
		} catch (RuntimeException re) {
			log.error("find all failed", re);
			throw re;
		}
	}

	public Question merge(Question detachedInstance) {
		log.debug("merging Question instance");
		try {
			Question result = (Question) getSession().merge(detachedInstance);
			log.debug("merge successful");
			return result;
		} catch (RuntimeException re) {
			log.error("merge failed", re);
			throw re;
		}
	}

	public void attachDirty(Question instance) {
		log.debug("attaching dirty Question instance");
		try {
			getSession().saveOrUpdate(instance);
			log.debug("attach successful");
		} catch (RuntimeException re) {
			log.error("attach failed", re);
			throw re;
		}
	}

	public void attachClean(Question instance) {
		log.debug("attaching clean Question instance");
		try {
			getSession().lock(instance, LockMode.NONE);
			log.debug("attach successful");
		} catch (RuntimeException re) {
			log.error("attach failed", re);
			throw re;
		}
	}
}