Hibernate封装类

 最近研究hibernate，写了一个对Hibernate数据访问的一个封装，现在贴出来，供大家分析讨论。

 package com.lynn.db.dao;

 import org.hibernate.Session;
 import org.hibernate.SessionFactory;
 import org.hibernate.cfg.Configuration;

 public class BaseDao {

     static Configuration conf = null;
     static SessionFactory factory = null;
     static Session session = null;
     static{
         try {
             conf = new Configuration().configure();
             factory = conf.buildSessionFactory();

         } catch (Exception e) {
             e.printStackTrace();
         }
     }

     /**
      * 获得Session连接
      * */
     public static Session getSession(){
         session = factory.openSession();
         return session;
     }
     /**
      * 关闭session连接
      * */
     public static void closeSession(){
         if(session!=null)
             session.close();
     }


 }

下面是封装的增、删、改、查

 package com.lynn.db.dao;

 import java.util.List;

 import org.hibernate.Criteria;
 import org.hibernate.FetchMode;
 import org.hibernate.Session;
 import org.hibernate.Transaction;
 import org.hibernate.criterion.Order;
 import org.hibernate.criterion.Restrictions;

 import com.lynn.page.PageInfo;


 public class HibernateDao {

     protected Session session = null;
     protected Transaction ts = null;
     protected Criteria criteria;

     /**
      * session保存方法
      * */
     public boolean save(Object obj){
         boolean check = false;
         try {
             session = BaseDao.getSession();//获得连接
             ts = session.beginTransaction();//创建事务

             session.save(obj);//保存对象
             ts.commit();//提交事务
             check = true;
         } catch (Exception e) {
             e.printStackTrace();
             ts.rollback();//出现异常则回滚事务
         }
         return check;
     }
     /**
      * session删除方法
      * */
     public boolean  delete(Object obj){
         boolean check = false;
         try {
             session = BaseDao.getSession();
             ts = session.beginTransaction();
             session.delete(obj);
             ts.commit();
             check = true;
         } catch (Exception e) {
             e.printStackTrace();
             ts.rollback();
         }
         return check;
     }

     /**
      * session修改方法
      * */
     public boolean update(Object obj){
         boolean check = false;
         try {
             session = BaseDao.getSession();
             ts = session.beginTransaction();
             session.delete(obj);
             ts.commit();
             check = true;
         } catch (Exception e) {
             e.printStackTrace();
             ts.rollback();
         }
         return check;
     }
     /**
      * session查询方法(抓取)查询所有
      * @return Criteria
      * */
     public Criteria QueryByFetch(String...fetch){

         try {

             if(fetch!=null && fetch.length>0){
                 for (int i = 0; i < fetch.length; i++) {
                     criteria = criteria.setFetchMode(fetch[i], FetchMode.JOIN);
                 }
             }
         } catch (Exception e) {
             e.printStackTrace();
         }
         return criteria;
     }

     /**
      * 根据单条件或者多条件查询
      * 至少2个参数，第一个为属性名，第二个为属性值
      * @return Criteria
      * */
     public Criteria QueryByProperties(Object...properties){

         try {
             if(properties!=null && properties.length>0){
                 for (int i = 0; i < properties.length; i=i+2) {
                     criteria = criteria.add(Restrictions.like((String)properties[i], properties[i+1]));
                 }

             }
             return criteria;
         } catch (Exception e) {
             e.printStackTrace();
         }
         return null;
     }

     /**
      * 查询所有
      * */
     public Criteria Query(Class c){
         session = BaseDao.getSession();
         criteria = session.createCriteria(c);
         return criteria;
     }
     /**
      * 将查询结果返回List
      * @return List
      * */
     public List QueryList(){
         try {
             return criteria.list();
         } catch (Exception e) {
             e.printStackTrace();
         }
         return null;
     }
     /**
      * 查询单个数据
      * @return Object
      * */
     public Object QueryUnique(){
         try {
             return criteria.uniqueResult();
         } catch (Exception e) {
             e.printStackTrace();
         }
         return null;
     }
     /**
      * 此类专门用于分页
      * */
     public Criteria QueryByPage(PageInfo pageInfo){


         return criteria.setFirstResult((pageInfo.getPageIndex()-1)* pageInfo.getPageSize())
         .setMaxResults(pageInfo.getPageSize());

     }
     /**
      * 此类专门用于排序
      * */
     public Criteria QueryByOrder(Order o){
         return criteria.addOrder(o);
     }

 }