EJB for OCPJWSD 6.0.

[ketan gote]

Hi


I am planning to give OCPJWSD 6.0. I have worked on web-service but have not much exposure to EJB, do i need to study first EJB.
If i don't know EJB should i try for OCPJWSD 5.0.

[Sujeeth Pakala]

You should know how different types of EJBs (Stateless and Singleton) are exposed as SOAP / RESTful web services.

[Himai Minh]

Sujeeth,
In Java Up and Running book, it introduced @Entity. And MZ's note mentions very little about @Singleton.
All I can do is to google @Entity and @Singleton to learn about them.

[Sujeeth Pakala]

In Java Up and Running book, it introduced @Entity.

Plese tell me which chapter it is mentioned ?

Normally @Entity annotation used in persistence application and they hold the data present in table. It is unsual to expose these objects as web services. Or am I wrong ?

[Himai Minh]

Sujeeth,
I am reading Chapter 6 of Java Web Service Up and Running. It has an example called FibNum.java. There is an @Entity annotation of this class.
This section teaches us how to deploy the FibNum in an ear file with persistency.xml in GlassFish.
I am still struggling with this example because I ran into oralce.toplink.essentials.database.DerbyPlatform is not found on GlassFish.

[Frits Walraven]

Hi All,

Let me get back to the original question

I am planning to give OCPJWSD 6.0. I have worked on web-service but have not much exposure to EJB, do i need to study first EJB.

No, you don't need to, but it will certainly help! A couple of topics from the EJB exam where also covered in the Web services exam. One of the things you learn from there is that you can only expose a Stateless Session Bean or Singleton Session Bean as a web service.

Forget about the @Entity though: this is not needed for the Web services exam (just in the book to make a nice example)

Regards,
Frits