Java

JavaTM Archive (JAR) Files

Documentation Contents
JAR (Java Archive) is a platform-independent file format that aggregates many files into one. Multiple Java applets and their requisite components (.class files, images and sounds) can be bundled in a JAR file and subsequently downloaded to a browser in a single HTTP transaction, greatly improving the download speed. The JAR format also supports compression, which reduces the file size, further improving the download time. In addition, the applet author can digitally sign individual entries in a JAR file to authenticate their origin. It is fully extensible.
JAR File Specification and Overview JAR Files and the Extensions Framework Jar Tool Reading and Writing JAR Files: API Specification

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