What file is .jar?

# What file is

.jar?

In the software field, a JAR file is a software package file format, built in ZIP format, with ".jar" as the file extension. It is usually used to aggregate a large number of Java class files, related Metadata and resource files into one file to facilitate development of Java platform applications or libraries.

JAR Features

The JAR file format provides many advantages and features, many of which are traditional compression formats such as Not provided by ZIP or RAR. They include:

Security

The contents of JAR files can be digitally signed. This way, a tool that recognizes the signature can selectively grant you software security privileges that no other file can, and it can also detect whether the code has been tampered with.

Reduce download time

If an applet is bundled into a JAR file, the browser can download the applet's class files and related resources in one HTTP transaction instead of downloading each applet. A file opens a new connection.

Compression

The JAR format allows you to compress files to increase storage efficiency.

Transport Platform Extensions

The Java Extensions Framework provides a way to add functionality to the Java core platform. These extensions are packaged in JAR files (Java 3D and JavaMail are developed by Sun Developed extended example).

Package Sealing

Packages stored in JAR files can optionally be sealed to enhance version consistency and security. Sealing a package means that all classes in the package must be found in the same JAR file.

Package Versioning

A JAR file can contain data about the files it contains, such as vendor and version information.

PortabilityThe mechanism for handling JAR files is a standard part of the Java platform core API. Recommended tutorials: "
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Java Tutorial

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