How to Create Executable JAR File (3 Methods Explained)

An executable JAR (Java Archive) file lets you run a Java application with a single click or command. Unlike standard JARs, executable JARs include a main class defined in the MANIFEST.MF file, making them self-runnable. In this guide, you’ll learn three methods to create executable JARs—using the command line, Maven, and Eclipse IDE.

Prerequisites

• Java Development Kit (JDK) installed (version 8 or later).
• Basic familiarity with Java programming.

Method 1: Create Executable JAR via Command Line

Step 1: Write a Java Program

Create a simple Java class with a main method. For example:

public class HelloWorld {  
    public static void main(String[] args) {  
        System.out.println("Hello, Executable JAR!");  
    }  
}  

Save it as HelloWorld.java.

Step 2: Compile the Java File

Open Terminal/Command Prompt and compile the code:

javac HelloWorld.java  

This generates HelloWorld.class.

Step 3: Create a Manifest File

The manifest defines the main class. Create a manifest.txt file with:

Main-Class: HelloWorld  

Note: Add a newline at the end of the file to avoid errors.

Make sure to save both HelloWorld.java and manifest.txt file in same location/folder.

Step 4: Build the Executable JAR

Run the jar command to bundle files:

jar cfm HelloWorld.jar manifest.txt HelloWorld.class  

• c: Create a JAR.
• f: Specify the JAR filename.
• m: Include the manifest file.

Step 5: Run the Executable JAR

Test it with:

java -jar HelloWorld.jar  

Output: Hello, Executable JAR!

Method 2: Create Executable JAR with Maven

Step 1: Configure the pom.xml File

Add the Maven JAR Plugin to your project’s pom.xml:

<build>  
    <plugins>  
        <plugin>  
            <groupId>org.apache.maven.plugins</groupId>  
            <artifactId>maven-jar-plugin</artifactId>  
            <version>3.3.0</version>  
            <configuration>  
                <archive>  
                    <manifest>  
                        <mainClass>com.codersathi.HelloWorld</mainClass>  
                    </manifest>  
                </archive>  
            </configuration>  
        </plugin>  
    </plugins>  
</build>  

Replace com.example.HelloWorld with your main class’s full package path.

Step 2: Build the JAR

Run:

mvn clean package  

The executable JAR will be generated in the target folder.

Method 3: Create Executable JAR in Eclipse

Step 1: Export the Project as a JAR

1. Right-click your project > Export > Java > JAR File.
2. Select resources to include and specify the JAR output path.

Step 2: Define the Main Class

1. In the export wizard, click Next until you reach the JAR Manifest Specification screen.
2. Check Generate the manifest file and specify your main class under Main Class.

Step 3: Finish and Run

Click Finish. Run the JAR via:

java -jar YourProject.jar  

Demo Video

Troubleshooting Executable JAR Issues

1. “No main manifest attribute”

• Solution: Ensure the Main-Class is correctly defined in the manifest.

2. “Could not find or load main class”

• Solution: Verify the main class’s package path matches the manifest entry.

Conclusion

You’ve now learned three ways to create an executable JAR file:

1. Command Line: Ideal for small projects.
2. Maven: Best for automated builds and dependency management.
3. Eclipse: Perfect for IDE users.

For advanced use cases, explore creating fat JARs or bundling apps into native executables.

Need help? Check out our guide on how to run JAR files