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NX: Usage of Magic Cookie

 
Nicholas Cheung
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I would like to ask, what is the usage of the Magic Cookie, which read from the 1st 4-byte in the data file.
Thanks
 
Andrew Monkhouse
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Hi Nicholas,
Some dumb end user could try and use your application to open their favourite MS Word document. Or they might try and open my database file instead of the database file that your program works with.
But in either of those two cases, the magic cookie that is read when your application first starts up will not match the magic cookie that is in your database file.
So you can check the magic cookie to ensure that the file your program is reading is indeed the correct database format.
Regards, Andrew
 
Nicholas Cheung
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Thus, I need to hard code the magic cookie in the program, or put it somewhere (in property file or constaints) in order to use it to verify whether the DB file is the correct one?
Thanks for advice.
 
Terry Martinson
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I hard-coded it rather than using property file.
See info in magic cookie thread for more information.
TJ
 
It is sorta covered in the JavaRanch Style Guide.
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