File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
http://aspose.com/file-tools
The moose likes EJB and other Java EE Technologies and the fly likes EJB - Fresher Question Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Java » EJB and other Java EE Technologies
Bookmark "EJB - Fresher Question" Watch "EJB - Fresher Question" New topic
Author

EJB - Fresher Question

Guru dhaasan
Ranch Hand

Joined: Sep 13, 2006
Posts: 126

Hi,

I am new to EJB and I am going thro "Enterprise Java Beans 3.1" (O'Reilly) book. In that it has been mentioned different terminologies like

  • EJB
    Bean
    Remote
    Local
    RemoteHome
    LocalHome
    RemoteBusiness
    LocalBusiness

  • Can anybody explain what are these terminologies mean in a java-layman tone....
    Also if you can give some details about how exactly EJB fits in an Enterprise appln. with an real-life-example-app would be great

    Thanks in advance


    Thanks, Shiv
    SCJP, OCE - JSP & Servlets Developer
    Jeanne Boyarsky
    internet detective
    Marshal

    Joined: May 26, 2003
    Posts: 30512
        
    150

    How far did you get in the book? A lot is explained there. Maybe if you tried to define the terms in your own words and we can confirm/clarify your understanding.


    [Blog] [JavaRanch FAQ] [How To Ask Questions The Smart Way] [Book Promos]
    Blogging on Certs: SCEA Part 1, Part 2 & 3, Core Spring 3, OCAJP, OCPJP beta, TOGAF part 1 and part 2
    Guru dhaasan
    Ranch Hand

    Joined: Sep 13, 2006
    Posts: 126

    Thanks Jeanne for your response.

    I just started on the book and I am at the end of Part I.

    To my understanding, from the client perspective (for ex., from a servlet)
    we can call an EJB. For this we will get an interface which can be used in the client and the corresponding implementation class will be there to serve the purpose (of the interface)

    What I dont understand is what these Local/Remote jargons are doing

    Please consider myself as a novice in the business comp. dev. field

    Awaiting your response
    Jeanne Boyarsky
    internet detective
    Marshal

    Joined: May 26, 2003
    Posts: 30512
        
    150

    Ok. You have the basic idea. Way back when, there were only remote interfaces. You got a remote home interface and used it to look up the bean's remote interface. The problem was that most people were deploying the servlet and "remote" ejb on the same server. This resulted in an unneeded performance overhead. As a result, they introduced local interfaces to cut that down and make ejb more efficient. Now, you have a choice between remote and local based on your actual needs.
    Guru dhaasan
    Ranch Hand

    Joined: Sep 13, 2006
    Posts: 126

    Thanks Jeanne...
    Got the idea
     
    I agree. Here's the link: http://aspose.com/file-tools
     
    subject: EJB - Fresher Question