• 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 Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Jeanne Boyarsky
  • Ron McLeod
  • Paul Clapham
  • Liutauras Vilda
Sheriffs:
  • paul wheaton
  • Rob Spoor
  • Devaka Cooray
Saloon Keepers:
  • Stephan van Hulst
  • Tim Holloway
  • Carey Brown
  • Frits Walraven
  • Tim Moores
Bartenders:
  • Mikalai Zaikin

Question about design pattern

 
Greenhorn
Posts: 8
Eclipse IDE Oracle Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I don't understand the question bellow

Which design pattern, when used, may introduce stale business data in the presentation tier?

A) Business Delegate

B) Transfer Object

F) Front Controller

The right answer is letter B. I don't understand this design pattern.

The source of this question is this mock exam OCEWCD (Java EE 6 Web Component) Training Lab
 
Ranch Hand
Posts: 37
Hibernate Spring Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
The Transfer Object is the copy of remote entity so during the time we data is send to view layer over the network it might be altered by some other program. So Transfer Object might have the stale state. E.g. the view requests for Employee details. The employee data is sent to view in a Transfer Object EmployeeDTO object. While the view gets it and process it some other program can update the Employee data and hence stale state of EmployeeDTO. I hope this helps.
 
Renato Carauta
Greenhorn
Posts: 8
Eclipse IDE Oracle Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I understand you can have a stale state when you using a Transfer Object. Thank you for your answer.
 
reply
    Bookmark Topic Watch Topic
  • New Topic