messagedao.java

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package com.olr.dao;

import java.util.List;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import com.olr.beans.Comment;
import com.olr.beans.Message;
import com.olr.util.Pager;

/**
 * A data access object (DAO) providing persistence and search support for
 * Message entities. Transaction control of the save(), update() and delete()
 * operations can directly support Spring container-managed transactions or they
 * can be augmented to handle user-managed Spring transactions. Each of these
 * methods provides additional information for how to configure it for the
 * desired type of transaction control.
 * 
 * @see com.olr.beans.Message
 * @author MyEclipse Persistence Tools
 */

public class MessageDAO extends HibernateDaoSupport implements IMessageDAO{

	public void deleteMessage(int messageId) {
		Object m=this.getHibernateTemplate().load(Message.class,new Integer(messageId));
		this.getHibernateTemplate().delete(m);
		
	}

	public void insertMessage(Message message) {
		this.getHibernateTemplate().save(message);
		
	}
	
	public Pager getMessagesPager(int userId,int pageSize,int pageNo){
Session session=this.getHibernateTemplate().getSessionFactory().openSession();
		
		Criteria criteria=session.createCriteria(Message.class);
		criteria.add(Restrictions.eq("userId", userId));
		int rowCount=((Integer)criteria.setProjection(
				Projections.rowCount()).uniqueResult()).intValue();
		criteria.setProjection(null);
		int startIndex=pageSize*(pageNo-1);
		criteria.addOrder(Order.desc("postdate"));
		criteria.setFirstResult(startIndex);
		criteria.setMaxResults(pageSize);
		List result=criteria.list();
		session.close();
		return new Pager(pageSize,pageNo,rowCount,result); 
	}
	
	public List<Message> getTopMessages(int userId,int topNum){
		Session session=this.getHibernateTemplate().getSessionFactory().openSession();
		Criteria criteria=session.createCriteria(Message.class);
		criteria.add(Restrictions.eq("userId", userId));
		criteria.addOrder(Order.desc("postdate"));
		criteria.setMaxResults(topNum);
		List result=criteria.list();
		return result;
	}
	
}