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JAR (Java ARchive, Java Archive), just install java software

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JAR (Java ARchive, Java Archive) is a platform-independent file format that combines multiple files into a single file. Users can bind multiple Java applets and their required components (.class files, images, and sounds) into a JAR file, which is then downloaded to the browser as a single simple HTTP (Hypertext Transfer Protocol) transaction , thereby greatly improving download speed. The JAR format also supports compression, reducing file size and further reducing download times. Alternatively, applet writers can digitally sign items in the JAR file to confirm their origin. It is written in Java and is fully backwards compatible with existing applet code and fully extensible.

This version of the Java platform extends the use of the JAR format. Enhancements include the ability to add a command-line JAR tool that can be used to create and update signed JAR files. At the same time, it also provides a new standard API (Application Programming Interface) for reading and writing JAR files. In addition, the Java Extensions Framework also provides a mechanism for handling extension dependencies and other third-party libraries packaged as JAR files.

JAR Features

JAR Guide.

Manifest and signing specifications

JAR files and extension architecture

The new extension mechanism in the Java platform packages extension classes in the JAR file format. To support the extension mechanism and related features such as sealing and version evolution of packages, we provide new manifest properties. See the extension specification for details.

Enhanced Jar tool

The Jar tool provides new -C and u options for creating and updating JAR files. See the Jar Tools Reference Page:

Jar Tools Reference Page (for Solaris)

Jar Tools Reference Page (for Windows)

Reading and Writing JAR Files : API specification

Package java.util.jar: Class used to create and read JAR files

Class java.net.JarURLConnection: Utilize the jar protocol to implement the URL to the JAR file (Uniform Resource Locators, Uniform Resource Locators) abstract class for connections.

Tutorials can be found at the Java Software site;

Java Archive (JAR) file format in Java Tutorials.

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International brand mobile phones... as long as they are not ultra-low-end... basically support Java. The only difference is in performance... Smart phones needless to say... Non-smart phones have the Java performance of Sony Ericsson phones The strongest... some models are even stronger than some smart phones...

Nokia

Motorola

Samsung

Sony Ericsson

All models support JAR format (except machines with blue screen and black and white screen).....