This week's book giveaway is in the HTML Pages with CSS and JavaScript forum.
We're giving away four copies of Testing JavaScript Applications and have Lucas da Costa on-line!
See this thread for details.
Win a copy of Testing JavaScript Applications this week in the HTML Pages with CSS and JavaScript forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Bear Bibeault
  • Ron McLeod
  • Jeanne Boyarsky
  • Paul Clapham
Sheriffs:
  • Tim Cooke
  • Liutauras Vilda
  • Junilu Lacar
Saloon Keepers:
  • Tim Moores
  • Stephan van Hulst
  • Tim Holloway
  • fred rosenberger
  • salvin francis
Bartenders:
  • Piet Souris
  • Frits Walraven
  • Carey Brown

Mock Exam Question : doubt

 
Greenhorn
Posts: 11
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi folks,

I am having one doubt regarding the following question which is from ejbcertificate.com

Which one of the following statements regarding the client view of exceptions received from an enterprise bean invocation is correct? Exceptions


1. The client can safely continue the transaction by retrying the operation if an application exception is received.
2. The client can safely continue the transaction by retrying the operation if an application exception is received, but only after checking the transaction has not been marked for rollback.
3. The client can safely continue the transaction by retrying the operation if a non-application exception is received.
4. A local client cannot continue a transaction if javax.transaction.TransactionRolledbackLocalException is received.
5. A remote client cannot continue a transaction if javax.transaction.TransactionRolledbackException is received.


Correct answer is 5 .I dont understand why only 5 why not 4 also. ??
The explaination provided by ejbcertificate is below but dont get the point.


Answer 5 is correct. javax.transaction.TransactionRolledbackException indicates to a remote client that the transaction has definitely been marked for rollback. Therefore it is pointless for the client to continue with the transaction, as the transaction cannot be committed.

Answers 1 and 2 are incorrect. It is potentially dangerous retrying to continue with a transaction after receiving an application exception because it is not always possible to determine the state of the enterprise bean. For example, if the container started a transaction just before invoking an enterprise bean with container-managed transaction and the enterprise bean throws an application exception and does not mark the transaction for rollback, the container commits the transaction before re-throwing the application exception to the client. In this scenario, it is not possible for the client to continue with the transaction on receiving the application exception.

Answer 3 is incorrect. The container will discard the bean instance if a non-application exception is thrown. Answer 4 is incorrect. javax.transaction.TransactionRolledbackException indicates to a local client that the transaction has definitely been marked for rollback. This exception is a subclass of javax.ejb.EJBException.
    Bookmark Topic Watch Topic
  • New Topic