How do I create a .JAR file?

Java Archive (JAR) files allow developers to package many classes into a single file. JAR files also use compression, so this can make applets and applications smaller.

Creating a .JAR file is easy. Simple go to the directory your classes are stored in and type :-

jar -cf myfile.jar *.class
If your application or applet uses packages, then you'll need to do things a little differently. Suppose your classes were in the package mycode.games.CoolGame - you'd change to the directory above mycode and type the following :- (Remember to use / on UNIX systems)

jar -cf myfile.jar .\mycode\games\CoolGame\*.class
Now, if you have an existing JAR file, and want to extract it, you'd type the following

jar -xf myfile.jar


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