Hibernate的HQL查询和工具类的增强

其实对Hibernate进行分析后可以发现，这个Hibernate对于对象的增加。删除，更新是差不多的，所以可以把他们整

合到一个工具类中去。还有就是，因为查询是很复杂的，所以对于数据库的查询，就有相对应的接口，类似于JDBC中

的PreparedStatemented这个类。下面我们先看一下工具类的增强

package com.bird.hibernate.test;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.cfg.Configuration;@SuppressWarnings("deprecation")public final class Hibernateutils {private static SessionFactory sf;private Hibernateutils(){}static{Configuration cfg = new Configuration();cfg.configure();sf = cfg.buildSessionFactory();}public static SessionFactory getSessionFactory() {return sf;}public static Session getSession(){return sf.openSession();}public static void add(Object entity){Session s = null;Transaction ts = null;try {s = sf.openSession();ts = s.beginTransaction();s.save(entity);ts.commit();} catch (HibernateException e) {if (ts != null)ts.rollback();throw e;} finally {if (s != null)s.close();}}public static void update(Object entity){Session s = null;Transaction ts = null;try {s = sf.openSession();ts = s.beginTransaction();s.update(entity);ts.commit();} catch (HibernateException e) {if (ts != null)ts.rollback();throw e;} finally {if (s != null)s.close();}}public static void delete(Object entity){Session s = null;Transaction ts = null;try {s = sf.openSession();ts = s.beginTransaction();s.delete(entity);ts.commit();} catch (HibernateException e) {if (ts != null)ts.rollback();throw e;} finally {if (s != null)s.close();}}}

然后是查询，使用hql是只面向对象的，不考虑什么表的问题。其他的和jdbc类是

package com.bird.hibernate.test;import java.util.List;import org.hibernate.HibernateException;import org.hibernate.Query;import org.hibernate.Session;import com.bird.domain.User;public class QueryTest {/** * @param args */public static void main(String[] args) {query("bird");}public static void query(String name){Session s = null;try {s = Hibernateutils.getSession();String hql="from User as use where use.name=?";Query query = s.createQuery(hql);query.setString(0, name);@SuppressWarnings("unchecked")List<Object> list = query.list();for(Object o: list){System.out.println(((User)o).getName());}} catch (HibernateException e) {throw e;} finally {if (s != null)s.close();}}}