sequencedao.java

这是一个网上购物店的源码

package org.digitstore.dao.daoimp;

import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.digitstore.dao.hibernate.HibernateUtil;

import net.sf.hibernate.*;

public class SequenceDao {
	
	private static Log log = LogFactory.getLog(Sequence.class);
	
	public int getNextId(String name) throws HibernateException {
	    Sequence sequence = new Sequence(name, -1);
	    Session s = HibernateUtil.currentSession();
		try{
			HibernateUtil.beginTransaction();
	    	List results = s.find("from Sequence seq where seq.name='" + name + "'");
	    	if ( results != null && results.size() > 0){
	    		sequence = (Sequence)results.get(0);
	    		sequence.setNextId(sequence.getNextId()+1);
	    		s.update(sequence);
	    		HibernateUtil.commitTransaction();
	    		return sequence.getNextId();
	    	}
	    	return 0;
	    }catch(HibernateException e){
	    	log.fatal(e);
	    	HibernateUtil.rollbackTransaction();
	    	return 0;
	    }finally{
	    	HibernateUtil.closeSession();
	    }
	    
	  }
}