Making a JAR

In the earliest days of Java, it was common to write simple applets that had only a single class file. More sophisticated applets might have dozens of class files as well as supporting files such as images and sounds. It became common to use the popular archive format, .zip, to bundle class files together. The Java Virtual Machine can read the .zip format, so it's not necessary to unzip these files.

Unfortunately, many users automatically unzip any arriving .zip file, breaking the applet. In Java 2, Sun provides tools for working with the Java archive format, JAR. A JAR file is still a .zip file, but includes a special manifest file to identify its contents. By using a suffix that is more clearly Java related, Sun has decreased the ...

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