http://www.j2ee.me/javaee/5/docs/api/javax/persistence/EntityManagerFactory. html http://www.javaworld.com/javaworld/jw-01-2008/jw-01-jpa1.html This annotation is used for the persistence purposes, meaning after retrieving the data from the Database System we store it in Java objects, so we use Java objects in our application instead of interrogating the Database(which is slower). Happy Coding!
-----Original Message----- From: java-ee-j2ee-programming-with-passion@googlegroups.com [mailto:java-ee-j2ee-programming-with-pass...@googlegroups.com] On Behalf Of stefan.brunig Sent: September-30-09 2:14 AM To: peeterbru...@hotmail.com Cc: j2ee passion Subject: [java ee programming] Re: Unknow Java statement hi peeter, in this context the '@' sign is a so-called annotation. it was introduced as 'metadata' facility in release 5.0 of the java platform. please check: http://java.sun.com/docs/books/tutorial/java/javaOO/annotations.html or http://java.sun.com/j2se/1.5.0/docs/guide/language/annotations.html as annotations are really useful and widely used, it is quite important to understand the basics. i suggest to play around with simple examples so you can see how annotations affect the behavior of your classes. -- stefan On Wed, Sep 30, 2009 at 8:48 AM, peeter brunch <peeterbru...@hotmail.com> wrote: > Hi, > > Can someone explain the meaning of the highlighted Java statement in the > following code especially the meaning of the @ sign in front of the > PersistenceUnit? Thanks. > > import database.BookDBAO; > import javax.servlet.*; > import util.Counter; > > import javax.ejb.*; > import javax.persistence.*; > > public final class ContextListener > implements ServletContextListener { > private ServletContext context = null; > > @PersistenceUnit > EntityManagerFactory emf; > > Regards, > Peeterbrunch > > > > > ________________________________ > Bing™ brings you maps, menus, and reviews organized in one place. Try it > now. > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Java EE (J2EE) Programming with Passion!" group. To post to this group, send email to java-ee-j2ee-programming-with-passion@googlegroups.com To unsubscribe from this group, send email to java-ee-j2ee-programming-with-passion+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/java-ee-j2ee-programming-with-passion?hl=en?hl=en -~----------~----~----~----~------~----~------~--~---
