itemdao.java

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/*
 * Created on 2005-9-4
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
package com.bid.hibernate;

import java.math.BigDecimal;
import java.util.List;
import net.sf.hibernate.*;

import com.bid.domain.Item;
import com.bid.exceptions.InfrastructureException;

/**
 * @author Ma Dou
 * 
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public class ItemDAO {

	/**
	 *  
	 */
	public ItemDAO() {
		super();
		// TODO Auto-generated constructor stub
		HibernateUtil.beginTransaction();
	}
	
	public void insert(Item item)throws InfrastructureException{
		Session session = HibernateUtil.currentSession();
		try {
			item = (Item) session.save(item);
		} catch (HibernateException ex) {
			throw new InfrastructureException(ex);
		}
	}
	
	public void update(Item item)throws InfrastructureException{
		Session session = HibernateUtil.currentSession();
		try {
			session.update(item);
		} catch (HibernateException ex) {
			throw new InfrastructureException(ex);
		}
	}

	public Item getItemById(Long itemId) throws InfrastructureException {
		Session session = HibernateUtil.currentSession();
		Item item = null;
		try {
			item = (Item) session.load(Item.class, itemId);
		} catch (HibernateException ex) {
			throw new InfrastructureException(ex);
		}
		return item;
	}

	public BigDecimal getMaxBidAmount(Long itemId)
			throws InfrastructureException {
		Session session = HibernateUtil.currentSession();
		BigDecimal maxBidAmount = null;
		try {
			String query = "select max(b.bidAmount)"
					+ " from Bid b where b.item = :item";
			Query q = session.createQuery(query);
			q.setLong("item", itemId.longValue());
			List results = q.list();
			if(results!=null && results.size()>0){
				maxBidAmount = (BigDecimal) q.uniqueResult();
			}else{
				maxBidAmount = new BigDecimal(0);
			}
			
		} catch (HibernateException ex) {
			throw new InfrastructureException(ex);
		}
		return maxBidAmount;
	}

}