Arun Kumar

Hi All,

Is IBM 257 still relevant. Since it is for websphere software 6.0, should i wait for an IBM certification for the latest webpshere server 6.1 release? Please advise.

Arun

Well done Bharat.

is it a coincidence?? i got 367 too
Arun

Great score Phil,
Congratulations. I am preparing for SCBCD too
Cheers
Arun

conrgatulations Vlad,

Arun

Actually i am looking into SCBCD too. My copy of the Head First EJB is on its way from Amazon. But after i looked into the IBM certificates offered on their WebSPhere platform, i think (atleast for me) that the certs from IBM will be more valuable, in the sense that you gain knowledge in J2EE and WebSphere, the most commonly used commercial J2EE platform.
No one wants to offer a job with just SCBCD. May be i am wrong here. If knowledge is your only motive, then IBM way also caters for that.
ACtually i want to take SCBCD and then proceed to websphere certs from IBM, and get back to SCEA. A Looooooooooooooooooooooooong way to go
On a side note, after getting 3 certs in Java, i still landed with a new job which requires Perl, PHP. No complaints about that though
Cheers
Arun
[ November 19, 2003: Message edited by: Arun Kumar ]

Yeah Phil, when are you going to upload the assignment. I know you got bored inbetween and went to SCWCD. Have you finished that?

I know this thread will be moved...
Anyway would like to thank Phil, Andrew, Max, Bharat, Vlad, Ulrik, Jim Yingst ... and a few more i might have forgotton.
Sorry i couldnt spend much time on this forum, since i got a new job and tied up with it ...
Thank you all
Arun
Details --
Section Max Actual Points Points General Con: 100 79 Documentation: 70 70 OOD: 30 30 GUI: 40 28 Locking: 80 80 Data Store: 40 40 Network Server: 40 40 Total: 400 367
Couldnt care less why i lost the points under general consideration, and GUI. Couldnt believe that i scored 70/70 for documentation. But to be honest my documentation was sh***y
TO all the 2 tier and 3 tier advocates, i did it using the 2 tier model.
[ November 17, 2003: Message edited by: Arun Kumar ]

Sun has reported a billion dollars lose this past quarter, and a billion more the next quarter. People predict that SUN might not survive for very long.
http://newsforge.com/newsforge/03/09/29/2234245.shtml?tid=3
So if this is all true, what happens to JAVA?
Arun

I cant remember the exact words given in the instruction. But the idea is, the suncertify.propeties file should be in your currentworking directory regardless of where your runme.jar file is.
Arun

Can get your answer by reading this FAQ

Are you using RMI or Socket solution. If RMI, how did you manage to use the DBMain interface as your remote interface?

Originally posted by Jim Yingst:

[b][Arun]And i read the Thread pointed out by Jim. It was really confusing. Some of the posts i wasnt sure if they are talking about "1 thread - 1 FileChannel" or "multiple threads - 1 file channel".
[Jim}Yea, sorry about that. In general I was trying to focus on multiple threads - 1 FileChannel in that discussion, and explaining why you still need synchronization in that case.

I know i am asking for too much, but Jim if you have time can you explain to me why do you think that FileChannel is not thread safe (Talking about multipe clients - single FileChannel).
From what i understood reading that long thread you had mentioned, implicit reads and write (where you dont set the position as a paramater in your read/write method) changes filechannel position during the process, so it is blocking. So these FileCHannel operations are thread safe.
Those reads/writes with position as a paramter (explicit position methods) can occur concurrently. But even then the read method (both in explicit and implicit position) is blocking according to the ReadableByteChannel API, so either way only one read can happen at a time. And explicit write method (with position as a paramter) is also blocking becuase it might lead to a change in file size. SO all the methods seems to happen only one at a time or can i say atomic. Or am i missing something?
Thankyou Jim
Arun

I was wondering if you have one client one RAF instance, what about the OS limit on number of filehandles allowed on a single file. I believe someof the OS have 256 as the limit. So in this case what will haappen when more than 256 clients connect to the server and opens more than 256 RAFs? Shouldnt this kind of design be concerned about such an issue? This was one of the reasons why i synchronized on a static RAF instance.
And i read the Thread pointed out by Jim. It was really confusing. Some of the posts i wasnt sure if they are talking about "1 thread - 1 FileChannel" or "multiple threads - 1 file channel".
Arun

I am using NIO for reads and writes in my Data class. For every read and write i synchronize on a static RAF instance.
The question is should i synchronize on RAF (as i am doing now) or the unique FileChannel it has? Currently in all my methods i use RAF.getChannel() to get the filechannel associated with the RAF. At the end of the method i am NOT closing the filechannel. If i close the filechannel at the end of the method, the next person who wants the filechannel for someother operation throws IOException.
Is there any advantage or disadvantage or any performance issues the way i am doing? Will there be any gains if i synchronize on FileChannel instead of RAF?
Arun

Hello bharat,
i might have misguided you ...
I checkd it out, that in unix the \\ works fine also. For example when i open the inputstream to load the property file,
FileInputStream in = new FileInputStream("\\root\\java\\project\\j2se\\code\\suncertify.properties");
This worked fine with \\ or / .
Notice the path it is \\ but without the drive letter. So if you have a properties file stored in a windows machine, the \\ will not cause any problmes in the unix machine. But i dont know about the drive letter. And anyway there is no guarantee the directory structure in the windows machine is going to be the same as the unix machine.
So your way of checking if the file exists should be fine..
SOrry about that ..
Arun