Hibernate模板

public final class HibernateUtil{
private static SessionFactory sessionFactory;

private static ThreadLocal session=new ThreadLocal();
private HibernateUtil(){
}
static{
Configuration cfg=new Configuration();
cfg.configure();//默认的是classpath
sessionFactory=cfg.buildSessionFactory();
}

pulic static Session getThreadLocalSession(){
Session s=(Session)session.get();
if(s==null){
s=getSession();
session.set(s);
}
return s;
}

 

public static void closeSession(){
Session s=(Session)session.get();
if(s!=null){
s.close();
session.set(null);
}

}

public static SessionFactory getSessionFactory(){
return sessionFactory;
}
public static Session getSession(){
return sessionFactory.openSession();
}


OpenSessionInView:作用：解决懒加载(session是否关闭)和事务问题(持久层中是否出现事务代码)

public class OpenSessionInView inplements javax.sevlet.Filter{
.........
public void doFilter(ServletRequest arg0,ServletResponse arg1,FilterChain arg2)throws IOException,ServletException{
Session session=null;
Transaction tx=null;
try{
session=HibernateUtil.getThreadLocalSession();
tx=session.beginTransaction();
arg2.doFilter(arg0,arg1);
tx.commit();
}catch(Exception e){
if(tx!=null)
 tx.rollback();
 throw new RuntimeException(e.getMessage(),e)
}finally{
HibernateUtil.closeSession();
}
}

.......

}

持久化类：

public class UserDAO{
public void addUser(user){
HibernateUtil.getThreadLocalSession().save(user);
}