How to Create a Jar File in Java

A Java class can be stored in a jar (Java Archive) file. The classes in a jar file are stored in a compressed format, much like a zip file. A jar file is a portable container of classes. To understand how to create a jar file in Java, follow these seven steps.

  1. Open your text editor and type in the following Java statements.
    Java Source Jar File
    This is a minimal program that serves the purpose of providing a class for your jar file.

  2. Save your file as

  3. Open a command prompt and navigate to the directory containing your Java program. Then type in the command to compile the source and hit Enter.
    Compile Source for Jar File Program

  4. Test your program prior to placing it in a jar file. Type in the command to run the Java runtime launcher and then hit Enter.
    Run The Jar File Program

  5. Now you will create a jar file containing your program. In your command prompt, make sure you're in the same directory as the previous step. Type in the following command and hit Enter.
    Run The Jar Utility

  6. The benefit of storing your class file in a jar file is that you can execute your class from any location on the file system. To illustrate this important point, navigate to the directory above the one where the class file is stored.

  7. Execute the Java runtime launcher with the cp (classpath) option. Notice that the path specified on the classpath option references the directory that contains the jar file.
    Run The Jar File Program
    You have successfully executed the class file stored in the jar file.
Author: Stephen Withrow

Stephen has over 30 years of experience in training, development, and consulting in a variety of technology areas including Python, Java, C, C++, XML, JavaScript, Tomcat, JBoss, Oracle, and DB2. His background includes design and implementation of business solutions on client/server, Web, and enterprise platforms. Stephen has a degree in Computer Science and Physics from Florida State University.

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