handler.java

提供列车车次查询功能

/*
 * Handler.java
 *
 * Created on 2008��11��28��, ����5:18
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package java.model;

/**
 *
 * @author Administrator
 */
import java.util.*;
import org.hibernate.*;
import java.hibernate_tier.HibernateUtil;
import java.hibernate_tier.Train;
import org.apache.log4j.Logger;
public class Handler {
    Query query;
    
    Logger log=Logger.getLogger("Handler.class");      //�����־Logger����
    Session session;
    Transaction tx;
    Train t=new Train();
    
    public Train getQueryResult(String code){
        session=HibernateUtil.currentSession();//���sessionʵ��
        tx=session.beginTransaction();        //���Transaction����
        
        try{
            query=session.createQuery("from Train t where t.trainCode=?");
            query.setString(0,code);
            List list=query.list();
            for(int i=0;i<list.size();i++){
                t=(Train)list.get(i);
            }
            tx.commit();//�ύ����ݿ�
            log.info("Obtain data successfully!");
            session.close();
            return t;
        }
        catch(HibernateException e){
            e.printStackTrace();
            log.error("error:",e);
            tx.rollback();
            return null;
        }
    }
}