hibernateservice.java

企业管理信息系统 myeclipse+mysql+hibernate+struts

/*
 * HibernateService.java
 *
 * Created on 2007年7月6日, 下午11:08
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.```````
 */

package com.emis.dbservice.hibernate;


import java.util.List;

import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
/**
 *
 * @author Administrator
 */
public class HibernateService {
    private static Configuration configuration;
    private static SessionFactory sessionFactory;
    
    // Create the initial SessionFactory from the default configuration files
    static {
        try {
            configuration = new  Configuration().configure();            
            sessionFactory = configuration.buildSessionFactory();
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }    
    
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
    
    public static Configuration getConfiguration() {
        return configuration;
    }
    
    public static void rebuildSessionFactory() {
        synchronized(sessionFactory) {
            try {
                sessionFactory = getConfiguration().buildSessionFactory();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    
    public static void rebuildSessionFactory(Configuration cfg) {
        synchronized(sessionFactory) {
            try {
                sessionFactory = cfg.buildSessionFactory();
                configuration = cfg;
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    
    public static Session getSession() {
        Session session = null;
        try {
            session = sessionFactory.openSession();
        } catch(Exception e){
            e.printStackTrace();
        }
        
        return session;
    }
    
    public static void close(){
        try {
            sessionFactory.close();
        }catch(Exception e){
            e.printStackTrace();
        }
    }
    
    public static void closeSession(Session session) {
        try {
            if (session != null) {
                session.close();
            }
        }catch(Exception e){
            e.printStackTrace();
        }
    }
    
    public static void rollbackTransaction(Transaction transaction) {
        try {
            if(transaction != null)
                transaction.rollback();
        }catch(Exception e){
            e.printStackTrace();
        }
    }
    
    /**
     * 得到多少行
     * @param sql
     * @return
     */
    public static int getRows(String sql) {
        int row = 0;
        Transaction transaction = null;
        Session session = null;
        try {
            session = HibernateService.getSession();
            transaction = session.beginTransaction();
            row = session.createSQLQuery(sql).executeUpdate();
            transaction.commit();
        }
        catch (HibernateException he) {
            he.printStackTrace();
            HibernateService.rollbackTransaction(transaction);
            row = -1;
        }
        catch (Exception e) {
            e.printStackTrace();
            row = -1;
        }
        finally {
            HibernateService.closeSession(session);
        }
        return row;
    }
    
    /**
     * 传hql语句,得到所有值
     * @param hql
     * @return
     */
    public static List execQuery(String hql) {
        List list = null;
        Transaction transaction = null;
        Session session = null;
        try {
            session = HibernateService.getSession();
            transaction = session.beginTransaction();
            list = session.createQuery(hql).list();
            System.out.println(hql + " 找到行数：" + list.size());
            transaction.commit();
        }
        catch (HibernateException he) {
            he.printStackTrace();
            HibernateService.rollbackTransaction(transaction);
            list = null;
        }
        catch (Exception e) {
            e.printStackTrace();
            list = null;
        }
        finally {
            HibernateService.closeSession(session);
        }
        return list;
    }
    
    /**
     * 分页
     * @param hql
     * @param firstPage
     * @param maxSize
     * @return
     */
    public static List execQuery(String hql, int firstPage, int maxSize) {
        List list = null;
        Transaction transaction = null;
        Session session = null;
        try {
            session = HibernateService.getSession();
            transaction = session.beginTransaction();
            Query query = session.createQuery(hql);
            query.setFirstResult(firstPage);
            query.setMaxResults(maxSize);
            list = query.list();
            transaction.commit();
            HibernateService.closeSession(session);
        }
        catch (HibernateException he) {
            he.printStackTrace();
            HibernateService.rollbackTransaction(transaction);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        finally {
            HibernateService.closeSession(session);
        }
        return list;
    }
}