Hibernate execute HQL statement create Hibernateutil class required by session

Importorg.hibernate.HibernateException; Importorg.hibernate.Session; Importorg.hibernate.SessionFactory; Importorg.hibernate.cfg.Configuration;  Public classHibernateutil {Private StaticSessionfactory sessionfactory =NULL; Static {          Try{Configuration cfg=NewConfiguration (). Configure (); Sessionfactory=cfg.buildsessionfactory (); } Catch(hibernateexception e) {//Todo:handle ExceptionE.printstacktrace (); }      }         Public Staticsessionfactory getsessionfactory () {returnsessionfactory; }         Public Staticsession getsession () {Session session= (Sessionfactory! =NULL) ? Sessionfactory.opensession ():NULL; returnsession; }         Public Static voidClosefactory (Session session) {if(Session! =NULL) {              if(Session.isopen ()) {session.close (); }          }      }  }  

1. This tool class can be used directly to get the session (static method) but it is important to note that this class is not thread-safe. Hibernate advocates thread-safe tool classes

2. The specific process can be understood to get the configuration object---> Get session factory sessionfactory---> Get session opensession (); The final call to the session of the various methods for data manipulation.

3. You can refer to the hibernate documentation for a very detailed introduction to the HIBERNATE-DISTRIBUTION-3.3.2.GA\DOCUMENTATION\MANUAL\ZH-CN Chinese version under the document folder

Document content

1.1.6. Startup and Helper Classes

It is time-to-load and store Some event  objects, but first The setup with some infrastructure code. You have the to-startup Hibernate by building a global org.hibernate.sessionfactory object and storing it somewhere for easy access in application code. A org.hibernate.sessionfactory  is used to Obtain org.hibernate.session  instances. A org.hibernate.session  represents a single-threaded unit of work. The org.hibernate.sessionfactory  is a Thread-safe global object that is instantiated once.

We'll create a HibernateUtil helper class that takes care of the startup and makes accessing the more org.hibernate.SessionFactory convenient.

 PackageOrg.hibernate.tutorial.util; Importorg.hibernate.SessionFactory; Importorg.hibernate.cfg.Configuration;  Public classHibernateutil {Private Static FinalSessionfactory sessionfactory =buildsessionfactory (); Private Staticsessionfactory buildsessionfactory () {Try {              //Create the sessionfactory from Hibernate.cfg.xml            return NewConfiguration (). Configure (). Buildsessionfactory (); }          Catch(Throwable ex) {//Make sure your log the exception, as it might be swallowedSystem.err.println ("Initial sessionfactory creation failed." +ex); Throw NewExceptionininitializererror (ex); }      }         Public Staticsessionfactory getsessionfactory () {returnsessionfactory; }    }