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The moose likes Developer Certification (SCJD/OCMJD) and the fly likes MANIFEST.MF file Big Moose Saloon
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Kevin Mc Cusker

Joined: Aug 06, 2003
Posts: 21
Hello there. Im new here and ive just downloaded the Boggitt & Scarper assignment. Could somebody please tell me what the file is? Also, im a little unsure about what im allowed/supposed to do with the db-2x1 file. To what extent am i allowed to change it or do i need to find a means of manipulating the contents without changing the format? After reading the instructions im reluctant to try anything through fear of doing something "WRONG"!! Help.
Kevin Mc Cusker

Joined: Aug 06, 2003
Posts: 21
hmmm. so its not important. no news is good news my old ma used to say.
Niall ORiordan

Joined: Jul 22, 2003
Posts: 15
Not sure what the manifest file is. I would imagine it is something with do with Jarring of the jar file you downloaded...That is what manifest files do.
As for your other question....
Take a copy of the .dat file...
DO NOT USE THE ORIGINAL TO MEES AROUND WITH or you will have to download the assignment again. Otherwise feel free to do what you like. Good luck.

Damian Ryan
Ranch Hand

Joined: May 09, 2003
Posts: 117
Mark, Niall
The file is a metadata file found in all JAR files. It contains key-value pair type entries, and, at a minimum tends to record the version of the JAR specification used by the archive (this is from memory, so I could be mistaken).
The entries in a manifest file have several purposes, but the one you are most likely to encounter later in your assignment is the Main-Class attribute, which you can use to make an executable JAR file. For example, if your main executable class was, you would have an entry in the file of your archive (called, say, my_archive.jar) like this:

then if you typed

the archive would be loaded and the main method in would be executed by the JVM. Packaging classes like this is helpful because it can avoid the need to state a classpath (either with the CLASSPATH environment variable or with the "-cp" option of the java command) because you can putt all the classes you will need into the JAR.
The file that comes inside the archive containing your assignment probably only contains a couple of entries about versioning information. You don't need to pay it any attention.
Hope this helps.

Always proofread carefully to see if you any words out.
Kevin Mc Cusker

Joined: Aug 06, 2003
Posts: 21
cheers niall & damian. ill get stuck right into this baby now. speak soon.
I agree. Here's the link:
subject: MANIFEST.MF file
It's not a secret anymore!