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JAR File


Joined: Jan 01, 2003
Posts: 1
Hello! to All,
When I run the ".jar" file using:
java -jar abc.jar
The following error appears:
Failed to load Main-Class manifest attribute from abc.jar.
I updated the file in the META-INF
folder of the abc.jar file, like that:
Manifest-Version: 1.0
(I added)
Main-Class: RF2
(Note: RF2 is the name of the class which contains the main() method, i.e, the applications entry point).
But, nothing happend.
Any advice will be regarded very very valueable.

Thanks a lot to everybody!
Avi Abrami
Ranch Hand

Joined: Oct 11, 2000
Posts: 1124

Hi ABC (or is that DEF?),
I didn't find any mention of JDK version or platform in your post, so I'm going to assume 1.4.1 on Windows, and refer you to the relevant documentation:
I'm also assuming that the "RF2" class is in the default package (i.e. _not_ in any package).
First you need to create a text file and put the following line in it:
Main-class: RF2
Note that you need to write it exactly as it appears above, and have an "empty" line after it (in other words, hit the <ENTER> key after typing the above line).
So, to re-iterate, open "Notepad" (since you are using Windows), type the line shown above, hit <ENTER>, and save the file (under any name you like).
Then create the JAR file. I don't know exactly what command you are using (since you didn't mention that, either), but it should start like this:
jar cmf myManifestFile abc.jar <rest of command...>
where "myManifestFile" is the file you created in "Notepad" (see above) and "abc.jar" is the name of the JAR file you wish to create. [Note: this assumes that "myManifestFile" is in the current directory.]
Et voila, you should now be able to (successfully) execute the following command:
java -jar abc.jar
Hope this has helped you.
Good Luck,
Dirk Schreckmann

Joined: Dec 10, 2001
Posts: 7023
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Dirk Schreckmann

Joined: Dec 10, 2001
Posts: 7023
You may want to take a look at Creating a JAR File.
I agree. Here's the link:
subject: JAR File