messagesdao.java

实现简单的群聊功能

package cn.edu.buaa.scse.liyi.network.hibernate.dao;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.hibernate.Query;

import cn.edu.buaa.scse.liyi.network.hibernate.bean.Messages;

public class MessagesDAO extends HibernateDAO
{
	public void addMessages(final Messages mes)
	{
		save(mes);
	}
	
	public void deleteMessages(final Messages mes)
	{
		delete(mes);
	}
	
	public void updateMessages(final Messages mes)
	{
		update(mes);
	}
	
	public Messages getMessagesById(final int mid)
	{
		return (Messages)getSession().get(Messages.class,new Integer(mid));
	}
	
	public List<Messages> getMessages(final int sender)
	{
		String hsql="from Messages where sender=?";
		Query query=getSession().createQuery(hsql);
		query.setInteger(0,sender);
		List<Messages> list=new ArrayList<Messages>();
		Iterator it=query.list().iterator();
		while(it.hasNext())
			list.add((Messages)it.next());
		
		return list;
	}
	
	public List<Messages> getNewstMessages(int lastid)
	{
		String hsql="from Messages where mid>:lastid";
		Query query=getSession().createQuery(hsql);
		query.setInteger("id",lastid);
		List<Messages> list=new ArrayList<Messages>();
		Iterator it=query.list().iterator();
		while(it.hasNext())
			list.add((Messages)it.next());
		
		return list;
	}
}