The Java Archive (JAR) file format enables you to bundle multiple files into a single archive file. Typically a JAR file contains the class files and auxiliary resources associated with applets and applications.
The JAR file format provides many benefits:
• Security. You can digitally sign the contents of a JAR file. Users who recognize your signature can then optionally grant your software security privileges it wouldn’t otherwise have.
• Decreased download time. If your applet is bundled in a JAR file, the applet’s class files ...