DB header format

[Bert Ley]

Hello,

I was wondering could somebody help me out or point me in the right direction. I've just started the SCJD. I was able to extract the first 3 values from the .db file but when I looked at the layout of the information in the .db file it appears as shown below(a partial screen dump from command prompt),

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

♦name location @ ♂specialties @ ♦size ♠ ♦rate ♣owner

-----------------------------------------------------
The different symbols stand for the 2 byte numerics wrapping the field names but it appears that the numerics are missing from after the 'name' field and before the 'location' field. Is this a problem with ht efile sent to me by SUN or should those valuse not be there. Any help is really appreciated.
thanks.

[Laura Williamson]

yes i have beenhere. use readByte, readShort, etc

[Vishwa Kumba]

Bert,
Aah....That name sounds too familiar!...
Welcome to the ranch and to the forum!(at last I get the lucky chance to welcome somebody in this forum )

The db file is a binary file, so it is different. It also contains a lot of non-printable ascii characters.You could use a Hex editor to read the data or write a small program to read the file contents.
As Laura suggested, use Java IO API to read/write the file contents. I am using RandomAccessFile for my assignment.You should also go thru your Data File Format section in your instructions document.That explains the data schema of the supplied database file.

[Bert Ley]

I was using readShort and readInt to get the first values and they worked fine. But then when I printed out the file values in DOS there were a few missing but then I used the Hex editor and they seem to be there alright. cheers for the help.

Bert

[Andrew Monkhouse]

Hi Bert,

Welcome to JavaRanch.

We don't have many rules here, but one we do have is the JavaRanch Official Policy On Displayed Names, which requires your displayed name to show both a first and a last name.

Could you please change your displayed name to meet this policy? You can change it here.

Regards, Andrew

[james airey]

i think the numerics in the db file are confusing.
if i remember correctly, some of them are genuinely numbers in hex form, and some of them go via a text format.

eg, the length of a field is a hex number, and needs to be read as such.
however the capacity of a room is a text number, so needs to be read as an int, and then cast as a char, or something like that.

i could be wrong though ...