passed developer exam 144/155!!

[balaji sambandam]

Hi guys,
I just checked the certification database and
I passed with a score 93%. 144/155.
Test: Sun Certified Developer for the Java 2 Platform
(310-027)
Date Taken: 2000-12-28 14:55:11.293
Grade: P
Score: 144
Comment: could have been awarded in each section and
the actual number of points you were awarded. This
information is provided in order to give you feedback
on your relative strengths on a per-section basis. The
maximum number of points you could have received is
155; the minimum to pass is 124. General
Considerations(maximum = 72) ...65
Documentation(maximum = 10) ...10 Object-Oriented
Design(maximum = 6) ...6 GUI(maximum = 20) ...16 Data
conversion program(maximum = 10) ...10 Server(maximum
= 37) ...37
Wish you all the best guys.!

Balaji

[Paul Smiley]

Congratulations! Make sure that you stay around here and help us 'students' out!

[Mike McGowan]

Congrats! Enjoy the New Year with your success.

[Jerry Pulley]

Balaji,
Good work! It's encouraging to hear from someone who actually finished.
Can you tell us a little about your implementation? No details please, just things like whether your locking used a client identifier and how you handled local/remote transparency.
Jerry
[This message has been edited by Jerry Pulley (edited December 31, 2000).]

[balaji sambandam]

Hi,
I used RMI for networking
and for locking I did not use any client id as I thought
sun didn't specify anything about it in its specs (And it's also
very obvious when we see parameters used in locking and unlocking methods). For local and remote modes I used
two different classes to handle the database calls from clients.

Originally posted by Jerry Pulley:
Balaji,
Good work! It's encouraging to hear from someone who actually finished.
Can you tell us a little about your implementation? No details please, just things like whether your locking used a client identifier and how you handled local/remote transparency.
Jerry
[This message has been edited by Jerry Pulley (edited December 31, 2000).]

------------------

[Sanjeev Kumar]

Congratulations! Enjoy success.

[Sarada Bhasker]

Congratulations Balaji!!!
I am thinking of doing groundwork for Java Developer Exam. Hope you will be around here to help us.

[Qi Chen]

Congrats, Balaji.
Since you said for locking you did not use any client id, I
am wondering how you achieved the following:
(1) from instruction:
If an attempt is made to unlock a record that has not been locked by this connection, then no action is be taken.
(2) from code comment of the unlock method:
Ignore if the caller does not have a current lock on the request record.
Thanks.

[balaji sambandam]

Hi,
All we need to know( inside the lock method) is whether a record
has been locked and We don't need to know who locked a record.
Each record has a record number (See the DataInfo class)
and we need to have some mechanism to keep track of the
list of record that are locked in lock method.
If a client calls unlock method with a record no(which is not
locked by any client), we don't need to take any action.
Anyway this is just my view. It couldn't have been implemented
in many different ways.
Hope this helps.
Balaji

Originally posted by Qi Chen:
Congrats, Balaji.
Since you said for locking you did not use any client id, I
am wondering how you achieved the following:
(1) from instruction:
If an attempt is made to unlock a record that has not been locked by this connection, then no action is be taken.
(2) from code comment of the unlock method:
Ignore if the caller does not have a current lock on the request record.
Thanks.

[Qi Chen]

Hi Balaji,
Thanks for your response.
I understand your opinion and I agree with you that the specs can be implemented in different ways, but do you really think your approach implemented the requirements I quoted?
More specifically, notice the word "by this connection" in (1), and the word "the caller" in (2).
I guess in your approach, a record locked by one caller of the method lock(int) can be unlocked by another caller of the method unlock(int).

[balaji sambandam]

Hi,
I know it's not a fool proof method. I didn't want to mess around with lock and unlock methods's parameter (as sun
prefers a simple solution to a compound one as suggested in the guidance document). I just wanted to implement both methods without any change in the signatures.
If every client follows this rule in order
1) lock
2) book the ticket
3) and unlock
there wouldn't be any problem. When a record is locked by the first client , it cannot be locked by another client. The next client will have to wait till the lock is released by the first guy. We have to make sure in the GUI that a client does n't call unlock method randomly. When a user confirms the booking, every client will have to first call lock method , book the ticket if necessary and finally call unlock method.
Hope this helps.

Originally posted by Qi Chen:
Hi Balaji,
Thanks for your response.
I understand your opinion and I agree with you that the specs can be implemented in different ways, but do you really think your approach implemented the requirements I quoted?
More specifically, notice the word "by this connection" in (1), and the word "the caller" in (2).
I guess in your approach, a record locked by one caller of the method lock(int) can be unlocked by another caller of the method unlock(int).

[This message has been edited by balaji sambandam (edited January 02, 2001).]

[Da Zhu]

Hi Balaji,
A question on the lock method:
public void lock(int record) throws IOException
Does your code possibly throw IOException? How?
Regards,
Da Zhu

[balaji sambandam]

Hi qi,
If there is an invalid record reference (i.e if
a client tries to lock record with record number
0 or less than -1 (-1 is DB lock) ) or if the user tries
to lock a record No that is not in the
database then I will throw an IO exception
Hope this helps

Originally posted by Da Zhu:
Hi Balaji,
A question on the lock method:
public void lock(int record) throws IOException
Does your code possibly throw IOException? How?
Regards,
Da Zhu

[This message has been edited by balaji sambandam (edited January 02, 2001).]
[This message has been edited by balaji sambandam (edited January 02, 2001).]

[Da Zhu]

Hi Balaji,
Thanks for your explaination. Although it looks strange that the lock method throws IOException, since all other public methods catch IOException and then throw DatabaseException, I will stick with the given signature. No reason to take the risk of modifying signatures.
One more question, did you format your data, say change the input data 11h65m to 12h5m? If yes, at which stage do you make such formating (during data conversion, in retrieving data from database, or in JTable column formating)? I know 11h65m looks silly, but I do not see anywhere in the instruction that asks for data formating.

[balaji sambandam]

I didn't change the format as it's not a requirement in
the spec.

Originally posted by Da Zhu:
Hi Balaji,
Thanks for your explaination. Although it looks strange that the lock method throws IOException, since all other public methods catch IOException and then throw DatabaseException, I will stick with the given signature. No reason to take the risk of modifying signatures.
One more question, did you format your data, say change the input data 11h65m to 12h5m? If yes, at which stage do you make such formating (during data conversion, in retrieving data from database, or in JTable column formating)? I know 11h65m looks silly, but I do not see anywhere in the instruction that asks for data formating.

[shivani anand]

Balaji,
First of all I should congratulate you for such a great acheivement.
Could you please write details about the asssignment given for Developer certification. This will help me to decide whether to take this exam or not.
Thanks in advance
Shivani

[balaji sambandam]

Hi,
You can find a very useful and descriptive explanation about the
assingment in developer section of "Java 2 Certification - Jamie Jaworski " book.

Originally posted by shivani anand:
Balaji,
First of all I should congratulate you for such a great acheivement.
Could you please write details about the asssignment given for Developer certification. This will help me to decide whether to take this exam or not.
Thanks in advance
Shivani

[Balaji Sadasivam]

Congratulations Balaji!!
Can you tell me the objectives of this exam?? The objective given in the Sun web-site is not clear. I need some specific topics.
Also can you recommend some study materials??
Is it necessary to study books related to "Object-Oriented Analysis and Design" ??
Please do reply.
Thanks
Regards
Balaji

[balaji sambandam]

You can read the following books and may serve as a
reference guide while you are doing the assignment.
Core Java volume 1 and Volume 2
Graphics JAVA Mastering JFC.
Java 2 Exam Guide - Barry Boone/william Stanek
You don't need to read the whole book. Read only chapters
which are needed to compelete assingment such as
RMI
Swing classes
sockets
I/O
LayoutManager
and etc...

And don't forget to read RMI tutorials and archives at
SUN site (if you plan to use RMI in your assingment)

Originally posted by Balaji Sadasivam:
Congratulations Balaji!!
Can you tell me the objectives of this exam?? The objective given in the Sun web-site is not clear. I need some specific topics.
Also can you recommend some study materials??
Is it necessary to study books related to "Object-Oriented Analysis and Design" ??
Please do reply.
Thanks
Regards
Balaji

[Balaji Sadasivam]

I am planning to use RMI in my assignment.
I have both volume 1 and 2 of Core Java. I can refer the rest at Borders.
Thank you very much for your suggestions.!
Regards
Balaji

Originally posted by balaji sambandam:
You can read the following books and may serve as a
reference guide while you are doing the assignment.
Core Java volume 1 and Volume 2
Graphics JAVA Mastering JFC.
Java 2 Exam Guide - Barry Boone/william Stanek
You don't need to read the whole book. Read only chapters
which are needed to compelete assingment such as
RMI
Swing classes
sockets
I/O
LayoutManager
and etc...

And don't forget to read RMI tutorials and archives at
SUN site (if you plan to use RMI in your assingment)