File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes Certification Results and the fly likes Doubt about wrapper classes Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Certification » Certification Results
Bookmark "Doubt about wrapper classes" Watch "Doubt about wrapper classes" New topic

Doubt about wrapper classes


Joined: Feb 08, 2001
Posts: 8
Can anybody tell me Is wrapper classes are included in the SCJP
one more thing, I want to KNow some thing about the keyword Transient, How we can use it? What is the use?
Thank you
Kathy Rogers
Ranch Hand

Joined: Aug 04, 2000
Posts: 104
Wrapper classes are included in the SCJP exam.
The transient keyword is used with serialization. You can serialize objects to transmit them in streams but when you do this, there may be sensitive class data that you don't want to transmit - for example, if you have a User object which has several attributes (name, password, age, address), you may not want to transmit the password for security reasons - you use the transient keyword to identify that data which is not included in an object's serialization. So you might declare password
private transient String password;
to indicate that it shouldn't be serialised.
Hope this helps,
[This message has been edited by Kathy Rogers (edited February 08, 2001).]
Shrini Kulkarni
Ranch Hand

Joined: Jan 12, 2001
Posts: 63
There is also one more aspect of transient key word. This is deals with Threads. A piece of transient data - tells compiler that several threads may be accessing it simulatneously. Hence data should be completely refershed everytime from memory and completely stored back after each access.
This is generally not mentioned while mentioning about transient data.
Hope this helps

Sun Certified programmer for Java2 platform.<BR>
Angela Poynton
Ranch Hand

Joined: Mar 02, 2000
Posts: 3143
I'm moving the to Programmers Certification Study!

Pounding at a thick stone wall won't move it, sometimes, you need to step back to see the way around.
I agree. Here's the link:
subject: Doubt about wrapper classes
It's not a secret anymore!