what is a jar file where is it used?
JAR file is the compressed file format. You can store many files in a JAR file. JAR stands for the Java Archive. This file format is used to distribute a set of java classes. This file helps you to reduce the file size and collect many file in one by compressing files. Downloading the files are become completed in very short duration of time because of reducing the file size. You can make the jar file executable by collecting many class file of your java application in it. The jar file can execute from the javaw (Java Web Start).
The JAR file format is based on the popular ZIP file format. Usually these file format is not only used for archiving and distribution the files, these are also used for implementing various libraries, components and plug-ins in java applications. Compiler and JVMs (Java Virtual Machine) can understand and implement these formats for java application.
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