JAR vs WAR: Difference and Comparison

Technology has become a great part of human life in several forms, like mobile phones, other electronic gadgets, several types of machinery, vehicles, etc., which have been necessary for human life. Living without them will now be quite difficult for the next generation.

To use such Technologies, the person does not need expertise. It just takes information about the gadget of machinery, and they are ready to use; for example, a mobile phone can be used by people of any age group easily for a 2-year-old kid for an 80-year-old person, the functionality of devices has been becoming so easy with several modifications, these modifications are done to make it apt for all age groups.

In devices like mobile phones or laptops, There are several functions which everybody does not use. Still, they are an important part of the device, and only a few technical experts know about them because they are not of daily use by an ordinary person, for example, archive files, zip folders, etc.

Key Takeaways

1. JAR stands for Java Archive and stores Java class files, libraries, and metadata.
2. WAR stands for Web Application Archive and is used for packaging and deploying web applications.
3. JAR files are used for general Java development, while WAR files deploy web applications on a server.

JAR vs WAR

A JAR (Java Archive) is a file with Java classes, metadata, and resources such as text and images grouped into one file. A WAR (Web application Archive) is a file used to distribute a collection of JAR files, JSP, Servlet, XML files, static web pages like HTML, and other resources that constitute a web application.

Comparison Table

Parameters of Comparison	JAR	WAR
Meaning	A file format, an acronym used for Java archive files, accumulates several Java class files and associates metadata and resources in one file for distribution.	A file format, an acronym for web application archive files. In technical terms, it is the collection of different files to distribute the collection of JAR files, JavaServer Pages, Java Servlets, Java classes, XML files, static web pages, etc.; in other words, all the resources that constitute a web application.
Extension used	Jar extension	War Extension
Types of files	Images, videos, etc.	HTML, GIFS, static web pages, etc.
Working	Accumulates files	Accumulates different resources.
Formats used for the creation	Any format	Servlet

What is JAR?

JAR is a file format, an acronym used for Java archive files; it is used to accumulate several Java class files and associate metadata and resources in one file for distribution.

We use a built-in ZIP format and have a JAR file extension. In simple terms, it compresses files like in a ZIP folder. It can be used as a general archive tool in devices.

Generally, the JAR file contains a number directory, audio, images, etc.; the output shows that JAR files contain a manifest default file automatically placed in the archive by the JAR tool. They are generally used in libraries, so these types of files are easy to access. 

JAR file is a package file format, EJB module is packaged which contains EJB descriptor and java class bean files, and they are packaged with JAR files. JAR files can be made manually as well.

Objects in files are Python classes that wrap file descriptors to make working with files more convenient and less error-prone.

JAR files are the only cross-platform archive format. On Microsoft Windows, the Java 2 runtime environment installation program registers a default association for JAR files, and thus, the JAR file on the desktop will automatically run with Java JAR.

The dependent extensions with applications will be loaded automatically.

What is WAR?

WAR is a file format, an acronym for web application archive files. In technical terms, it is the collection of different files to distribute the collection of JAR files, Java Server Pages, Java Servlets, Java classes, XML files, static web pages, etc.; in other words, all the resources that constitute a web application.

The advantage of using the WAR file is that it accumulates all the files in one single unit, so it takes less time for the user while transferring a file from client to server. WAR files can be made manually as well.

WAR files are deployed to a JSP engine or a servlet. This file type also contains a WEB-INF directory, the Web.xml, and a deployment descriptor. 

The directory structure of web application comprises two types; one is the Html/XML files, which are mainly images, videos, JSP pages, applets, etc., and the other part is the WEB-INF directory containing tag library descriptor files and the deployment descriptor.

WAR files are packaged with WAR extension and contain GIFs as well. WAR files are located in the web apps directory. WAR files may store different resources in different applications, which might create a hassle. To use files located in WAR files, the user must unzip the folder.

Main Differences Between JAR and WAR

1. JAR is a file format, an acronym used for Java archive files; it is used to accumulate several Java class files and associate metadata and resources in one file for distribution; on the other hand, WAR is a file format, an acronym for web application archive files. In technical terms, it is the collection of different files to distribute the collection of JAR files, Java Server Pages, Java Servlets, Java classes, XML files, static web pages, etc.
2. JAR files are packaged with jar extension; on the other hand, WAR files are packaged with WAR extension.
3. JAR files can accumulate different files; however, WAR files are confined to web applications.
4. JAR files contain EJB modules; on the other hand, WAR files contain JSP files, servlets, HTML, GIF, etc.
5. JAR files can be created manually with any format; on the other hand, WAR files can be created from servlets with a specific format.
6. JAR files are easy to access; on the other hand, WAR files are miscellaneous files which might create a hassle for the user.

References

1. https://dl.acm.org/doi/abs/10.1145/301631.301676