File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
http://aspose.com/file-tools
The moose likes Developer Certification (SCJD/OCMJD) and the fly likes ouch...... room for improvement Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Certification » Developer Certification (SCJD/OCMJD)
Bookmark "ouch...... room for improvement" Watch "ouch...... room for improvement" New topic
Author

ouch...... room for improvement

Robert Benson
Ranch Hand

Joined: Apr 04, 2010
Posts: 56
just got my results, failed unfortunatley:


Failed 314

Considerations (maximum = 100): 99
Documentation (maximum = 70): 70
O-O Design (maximum = 30): 30
GUI (maximum = 40): 31
Locking (maximum = 80): 44
Data store (maximum = 40): 40
Network server (maximum = 40): 0

Major point loss in record locking code. It is possible for 2 threads to lock the same record.


This report shows the total points that could have been awarded in each section, and the actual number of points you were awarded. This is provided to give you per-section feedback on your strengths. The maximum possible score is 400; the minimum to pass is 320.


I can accept the fail, but it seems strange to have been marked well with the other areas (nearly maximum in 4 sections) but to get 0 for the network server leaves me a bit perplexed.

It says my main point loss was with the record locking (44/80) but this is not true, my main point loss was with the network server (0/40).

I spent a bit of time with the locking so thats disappointing.
0 points for the network server. Room for improvement here. That serves me right for using a socket solution.
The good side is there are 9 points to pick up with the gui, so if I rework the display that should get me over the line with a resubmit.

Back to the drawing board. Will sit and think for a while before deciding how to move forward.




SCJP 6 , OCMJD 6 ,
http://www.robertbenson.ie/
Roberto Perillo
Bartender

Joined: Dec 28, 2007
Posts: 2264
    
    3

Howdy, Robert.

Champ, don't give yourself a hard time. What I can tell you is that it is not possible to win all the time. Don't feel disappointed!

No, it is really really weird that you got 0 for your server. Does your solution include a server that can be started, and then it expects calls from clients? Is it able to handle multiple requests? Does it use the Data object correctly so that it is not possible to have 2 clients locking the same record? Maybe there's a chance that they graded your solution incorrectly, so if you are sure about these points, you may ask a second evaluation of it, so you don't have to spend more money.

Also, if you still have to correct your solution, you can still stay with RMI. I used it and got 40 points for my server.


Cheers, Bob "John Lennon" Perillo
SCJP, SCWCD, SCJD, SCBCD - Daileon: A Tool for Enabling Domain Annotations
Andy Schmid
Greenhorn

Joined: Jan 14, 2009
Posts: 6
Robert, this are really bad news. I am feeling with you - especially because i have recently (few days ago) submitted my assignment and waiting for the result now.
I have to admit that i am a bit scared now ....
My thoughts are with you.
Andreas
Piotr Nowicki
Ranch Hand

Joined: Jul 13, 2010
Posts: 610

Robert - I'm sure that you'll be successfull with your second attempt And btw - "That which does not kill us makes us stronger" as Nietzsche said :-)

Out of curiosity - did you test your lock mechanism with your own the test cases or with the JavaRanch ones?

I'm also interested why did they give 0 points in your networking part...

Cheers!


OCP Java SE 6 Programmer, OCM Java SE 6 Developer, OCE Java EE 6 JSPSD, OCE Java EE 6 EJBD, OCE Java EE 6 JPAD, Spring 3.0 Core Professional.
Elchin Asgarli
Ranch Hand

Joined: Mar 08, 2010
Posts: 222

I am also surprised with 0 for network server. To me 0 means that it was totally nonfunctional, but wouldn't that lead to automatic failure?


Personal page, SCJP 6 with 91%, SCWCD 5 with 84%, OCMJD
Raf Szczypiorski
Ranch Hand

Joined: Aug 21, 2008
Posts: 383
Robert Benson wrote:The good side is there are 9 points to pick up with the gui, so if I rework the display that should get me over the line with a resubmit.

I don't know if you are just joking or not, but the next time you submit someone completely else might grade the assignment, and they will probably not know that it is your second attempt, so the point might be wildly different for each section - it's all about the taste of the person who grades.
Good luck in the future.
Roel De Nijs
Bartender

Joined: Jul 19, 2004
Posts: 5207
    
  12

Hi Robert,

I'm sorry to hear that you failed!

First of all, I would not try to improve the GUI, because that part of the assignment is quiet hard to get a maximum score, so it's very unlikely to pass with a resubmission by just improving the GUI.

Major point loss in record locking code. It is possible for 2 threads to lock the same record.

If it is indeed possible for 2 threads to lock the same record, you have to improve the lock/unlock methods, because there is a flaw in your implementation (maybe in combination with your socket solution, which might explain the 0/40 score). So I would start here. And if you have any doubts/questions, a complete java community is here to help you

As a side note: the 44/80 score was (in pre-Oracle days, when you always got your score) a very frequent score. Also perfect scores on documentation, o-o design and data store were common. The sections were point loss was most common are considerations, gui and locking

Good luck!
Kind regards,
Roel


SCJA, SCJP (1.4 | 5.0 | 6.0), SCJD
http://www.javaroe.be/
Roberto Perillo
Bartender

Joined: Dec 28, 2007
Posts: 2264
    
    3

Pedro Kowalski wrote:Out of curiosity - did you test your lock mechanism with your own the test cases or with the JavaRanch ones?


Well champ, the tests I proposed only test the Data class. It looks like the problem was with his server... if it doesn't use his Data class correctly, then the tests would not be able to get this problem.
Robert Benson
Ranch Hand

Joined: Apr 04, 2010
Posts: 56
Thanks for all your kind words and encouragement.
I for one do not give up that easily and I will go for it again.
Dont let my fail put anyone off. Im a COBOL / PL1 programmer trying to make the switch to Java. Ive never written a line of Java professionally and I only got into it since April, so Im a real newbie!

My server side was functional and "looked ok" to me (worth at least 6 points IMHO ), but someone did not like what I was doing.

It's just a matter of reworking and resubmitting.

In a way its kind of validated the worth of the certificate for me.
Robert Benson
Ranch Hand

Joined: Apr 04, 2010
Posts: 56
I got my resubmission results back today and I am delighted to say that I passed.

I took a few days off and then did a post-mortem on the assignment.
The error was immediately obvious when I looked at the code with fresh eyes.
My lock mechanism was not correct ,while the change that I made was small, it had a major influence on my result.

What did I learn from this:

1. Your lock mechanism is either 100% right or 100% wrong, there is no in between. If your lock does not work you will fail the assignment!

2. Understand the output from the tests provided by the ranchers. Don't just think that because you have run tests that your assignment worked. Understand what it is you are looking for before you do the tests and understand the output results.

3 "act in haste, repent at leisure". Dont be in too much of a hurry to submit and get the project out of the way. I think that you can go code blind before you submit and miss errors.
It is worth while to step back and take a break for a few days and look at the code with a fresh outlook. Mistakes will be easier to spot.

4. At least I know the breakdown of my marks for the other sections, so I'm happy with the outcome. (The only problem is it costs $300 for the resubmit).

Roberto Perillo
Bartender

Joined: Dec 28, 2007
Posts: 2264
    
    3

Alright champion, congrats for the achievement!

1. Your lock mechanism is either 100% right or 100% wrong, there is no in between. If your lock does not work you will fail the assignment!


Well, in the past, when we were able to see the score, there were some 44/80. I don't know exactly what that means, but there's one thing we can be sure of: if there's a remote possibility of deadlock, then the candidate will fail!

Now, how about opening a brand new thread with the good news?!
David Byron
Rancher

Joined: Jan 20, 2009
Posts: 172

Robert Benson wrote:I got my resubmission results back today and I am delighted to say that I passed.


Congrats! Your persistence has its reward.

What did I learn from this:

1. Your lock mechanism is either 100% right or 100% wrong, there is no in between. If your lock does not work you will fail the assignment!


As Yoda once said, "Lock or lock not. There is no luck."


SCJD 6, OCPJP7, Baroque Potion, G+
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: ouch...... room for improvement