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URLyBird Database file query

M Jay
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Joined: Sep 21, 2004
Posts: 66
In the specifications, it says that I need to create the DB file from scratch and ignore the one I got from them(but submit it back to them with the solution)... what's the point of the file then? and how do I create the new one?? should it be in txt format or like the one I got (.db) ?

Any help appreciated.


SCJP J2SE 1.4<br />SCBCD J2EE 1.3
Anton Golovin
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Joined: Jul 02, 2004
Posts: 476
Originally posted by M Jay:
In the specifications, it says that I need to create the DB file from scratch and ignore the one I got from them(but submit it back to them with the solution)... what's the point of the file then? and how do I create the new one?? should it be in txt format or like the one I got (.db) ?

Any help appreciated.


Mine says I need to reimplement database code from scratch. Please check your instructions, I bet you have same ones. What I read this to mean is that I need to write a data-management system that can read and write in the datafile format which is provided to me.


Anton Golovin (anton.golovin@gmail.com) SCJP, SCJD, SCBCD, SCWCD, OCEJWSD, SCEA/OCMJEA [JEE certs from Sun/Oracle]
M Jay
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Joined: Sep 21, 2004
Posts: 66
Oh so it means that I still use the provided file, but I reimplement(the existing database code which the company is using which I don't have) from scratch!?!?! that is quite confusing! so basically reimplement the DB interface that I'm provided with! cool!

how do I open and view the supplied .db file? I tried opening it with notepad but it looked quite confusing??

Thanks for the clarification
Anton Golovin
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Joined: Jul 02, 2004
Posts: 476
Originally posted by M Jay:
Oh so it means that I still use the provided file, but I reimplement(the existing database code which the company is using which I don't have) from scratch!?!?! that is quite confusing! so basically reimplement the DB interface that I'm provided with! cool!

how do I open and view the supplied .db file? I tried opening it with notepad but it looked quite confusing??

Thanks for the clarification


I use Notepad to view the text entries. The binary entries show as squares, or not at all. There must be binary viewers out there.
M Jay
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Joined: Sep 21, 2004
Posts: 66
Thanks for all of that Anton.

How far are you with your assignment? I got mine two days ago. How did u go about it? did you implement the DB first, then the GUI, then the Network connection? I'm pretty confused at the moment :-S
Anton Golovin
Ranch Hand

Joined: Jul 02, 2004
Posts: 476
Originally posted by M Jay:
Thanks for all of that Anton.

How far are you with your assignment? I got mine two days ago. How did u go about it? did you implement the DB first, then the GUI, then the Network connection? I'm pretty confused at the moment :-S


I was the same way you are two days into my assignment. Don't worry, you will do ok. My progression has been: data-management system, local gui, server. Once you write the data management system and test it for concurrency, you are done. The rest is purely elementary. I am done with my assignment save for some code in my RoomTableModel for the GUI and some event-handling code in the GUI. This forum offers a lot of opportunity to ask questions, and it helped me to get the assignment done.
M Jay
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Joined: Sep 21, 2004
Posts: 66
Cool so how long did it take you in terms of hours/days? what was the hardest part in your opinion?
Anton Golovin
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Joined: Jul 02, 2004
Posts: 476
Originally posted by M Jay:
Cool so how long did it take you in terms of hours/days? what was the hardest part in your opinion?


I don't have a lot of Java programming experience, so for me, writing the data-management system was the hardest part. I spent about two months on the project, or about 100 hours. Concurrency, actually, was not very hard to write thanks to Java's support for it. What was hard was looking at the scope of things to be done. Finally, I broke the project into parts and did them one by one. That way, I could complete a part, test it, and come away knowing I accomplished something. So I built the project from little bits into a whole.

I would note that overcomplication was the hardest part to deal with. It is possible, of course, to put out a grand application, one which is extensible, maintainable and professional. But the project does not require it. It requires a simple application with rudimentary GUI. What it is looking for, IMHO, is working code and documented problem-solving process.

Of the data class, I would pay special attention to multi-threading behavior of the data logic vs. business logic. Some methods in the data logic do not guarantee correct information when called from methods of the business logic (For instance, find method returns correct record numbers, but by the time these records are read, they are not guaranteed to match the search criteria. Or, the create method may malfunction in some situations, so it finds a record number to overwrite, overwrites it, and, as it turns out, overwrites a valid record.) All of these issues will make you think, and all of them are perfectly solvable in an elegant fashion. Also, this project benefits from simple design patterns, such as Adapter and MVC. I did not use any more design patterns because, in my view, it would overcomplicate the project.

[ September 23, 2004: Message edited by: Anton Golovin ]
[ September 23, 2004: Message edited by: Anton Golovin ]
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: URLyBird Database file query
 
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