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Bojan Knezovic

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Recent posts by Bojan Knezovic

Originally posted by Filipe Pomar:
Guys,

The specs for Part II describe two actors: TA and C. Even though both can purchase items on the system, in practical terms they could be doing it to another person, say his/her daughter or colleague. My questions would be: did you create a third actor called user that was a generalization of TA and C? Could I do that wrt the specs? How did you solve this issue?

Your thoughts are much appreciated.

Regards,
Filipe




I was always recommended to model only direct interaction with the system - it doesn't matter if the reservation is for daughter or colleague. You are modeling a system and users that use that system directly.

Regarding generalization, it's almost always possible to generalize actors and it depends on the situation but, again AFAIK, it's not a recommendable practice.

HTH,
Bojan
Manish,

I took the first part this morning and I scored 89%.

Regarding the design pattern questions - they are VERY easy (or at least they were in my case - I scored 100% there). They are much clearer than the mocks and as far as I could see, there were no "gray areas" - i.e. no cases where you can apply two or more of the listed ones.

I got five negatives, I guess they were mostly scenario based ones. I had read posts of the people saying there are some questions that are difficult to understand or not clear but I supposed Sun had already taken care of that. Well - obviously they did not.

I can say that my English is fairly good but there were at least two or three question where I did not understand the scenario. One was VERY confusing and it didn't even include any of the "special" things - pure design and common sense. I bet I missed that one!

The time was not a problem as 75 minutes were more than sufficient in my case. I even could re-pass the whole test two times.

So, off to the second part now. I wish you luck! And prepare some mind reading techniques!


Bojan
Do Home interfaces necessarily declare at least one create() method for entity beans? What if I don't want to permit creation of new entities?

The same goes for remove().

Thanks,
Bojan
Hi Manish!

I have not given the first part but I expect to do so in a 10-15 days (I'm terribly short with time these days). If you still need the answers by that time I will let you know about my experience.

Regarding the materials, for EJB's I used Head First to repass it, for Design Patterns GoF book (very good!) and for Common Architectures I couldn't find anything better than the Paul Allen's book. Actually I find it quite interesting except that it has A LOT info not needed on the exam (I think). But as my goal is not only to prepare for the exam it's not too bad.

And of course, all the notes you can find here or on the yahoo groups.

Bojan
You are correct, I never understood the question was focused on computer components and not the computer itself.

And in the other scenario you mention I found the Builder pattern to be the best match. It's used for creation of complex objects and a computer configuration can be perceived as such. Once the user has chosen what components he wants (and this indeed can be Prototype) a ConcreteBuilder can be created and the Director invokes corresponding methods and vo´┐Żla...

As you can see, in my opinion, Prototype can be a valid choice in both cases you mention. In the second case, you should choose between Prototype and Builder. What is the question? What is the best choice for that question? I have no idea. :roll:

Anyway, this is just a mock and they're known for not being too reliable (it's one of the 288 questions, right?). I'm just hoping the exam is more clear on what the questions are.

Bojan
Hi!

I've been doing some reading about Security and found in a couple of places that symmetrical encryption is faster than asymmetrical. However I couldn't find any explanation. I suppose there's some heavy math behind it so I'd be grateful if anyone can drop me a two or three line explanation..

Thanks in advance,
Bojan
It's weird, I know.

The data is coming in batch processes that are used by other systems as well. Actually I might say they are built for other systems and we're just hooked up there and using them for our app so we don't have much of the control over them.

One solution might be to decouple the code from the DB and use views, stored proc's etc. But for that I need to know what it the impact of using various schemas, if any... Hence the question. ;)

Thanks,
Bojan
Hi!

I was wondering what might be the pros & cons of separating one app's data in multiple schemas (based on years for example)? The other solution might be to keep it all in one schema and have a naming convention. This is necessary because the data types and length in one (or various) table(s) might vary from year to year.

BTW it's Weblogic on Oracle.

Thanks in advance,
Bojan
Thanks guys! This really is a list... it will take some time to chech 'em all!
15 years ago
Hi guys!

I was wondering if someone could recommend a real time monitoring tool for j2ee apps (availability, performance, response time, etc). Preferably something free / open source.

I'm also interested about experiences in some type of home-grown solution - i.e. apply some sort of design (pattern??) that permits plugin something that could inform of performance/availability problems.. perhaps something modular that can be changed or even turned off if found not to be necessary. Of course, with minimal impact on the real functionality.

Any thoughts?

Thanks!
15 years ago
Hi all,

I'm looking for a solution to the following problem: we have a JVM1 in a app. server and JVM2 on web server. When something happens (an event fires) in AS I need to contact some object in JVM2. Now, I'm thinking JMS rather than RMI - can anyone point out which one is better and why?

To make things more interesting, most likely the clustering architecture will be involved.

I'd appreciate a comment, a simple example, whatever from someone that has already seen a situation similar to this one.

TIA,
Bojan

Originally posted by Eugene Kononov:
com.crystaldecisions.sdk.framework
Class CrystalEnterprise
java.lang.Object
|
+--com.crystaldecisions.sdk.framework.CrystalEnterprise

static ISessionMgr getSessionMgr()
Returns the singleton ISessionMgr object.


Well, in this javadoc, there is no mention of any kind of exception thrown from the getSessionMgr() method. Looks like
some people call it as such, outside of the try-catch block, and without declaring the specifying it in the "throws" clause.

Perhaps SDKException is not really an exception in a JLS sense, but rather a misnamed class that has some "exceptional" purpose?




It ocurred to me too, but the BEA Workshop is very clear:

"ERROR: This expression can throw an exception com.crystaldecisions.sdk.exception.SDKException..."


OTOH, there are examples out there with the same piece of code working... that's why I was wondering if there was a change in the JLS or something. Don't get it really.
17 years ago
For the curious ones:


com.crystaldecisions.sdk.exception
Class SDKException
java.lang.Object
|
+--AbstractException
|
+--com.crystaldecisions.sdk.exception.SDKException





com.crystaldecisions.sdk.framework
Class CrystalEnterprise
java.lang.Object
|
+--com.crystaldecisions.sdk.framework.CrystalEnterprise

static ISessionMgr getSessionMgr()
Returns the singleton ISessionMgr object.




The code in question should be something like this:






I mean there are a few examples out there (not to mention the documentation that comes with tho product) that have the very same syntax that doesn't work in my workshop. I was wondering if there was a "change" in the near past in the JLS or something that made this impossible...?

Duhhh.... back to the search for another product.


Thanks for the help, guys.
17 years ago
I'm trying to log on to Crystar Enterprise 10 server:



The getSessionMgr() method throws SDKException which extends AbsstractException which in turn extends java.lang.Object - not Exception, not even Throwable. Obviously I need to put the above statement in a try/catch block, but if I write something like



the compiler is unhappy bacause SDKException is not Throwable and therefore cannot be caught. If I quit the line, it's unhappy again because the method might throw the darned SDKException!

Has anyone seen something like this? How do I solve it?

TIA,
Bojan
17 years ago
Hi guys, thanks for the replies, I have succesfully installed the Crystal in Workshop and everything seems fine except that I can't alter the report from code - seems I can't change the report source programatically.
I have found an example in C# but all the namespaces are different and the ReportDocument class doesn't even exist in Java. Could it be that CR implementation for .NET is so much better that the one for Java?