jar - How do I create executable Java program?

Question

This question already has answers here:

Answer 1

You can use the jar tool bundled with the SDK and create an executable version of the program.

This is how it's done.

I'm posting the results from my command prompt because it's easier, but the same should apply when using JCreator.

First create your program:

$cat HelloWorldSwing.java
    package start;

    import javax.swing.*;

    public class HelloWorldSwing {
        public static void main(String[] args) {
            //Create and set up the window.
            JFrame frame = new JFrame("HelloWorldSwing");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            JLabel label = new JLabel("Hello World");
            frame.add(label);

            //Display the window.
            frame.pack();
            frame.setVisible(true);
        }
    }
    class Dummy {
        // just to have another thing to pack in the jar
    }

Very simple, just displays a window with "Hello World"

Then compile it:

$javac -d . HelloWorldSwing.java

Two files were created inside the "start" folder Dummy.class and HelloWorldSwing.class.

$ls start/
Dummy.class     HelloWorldSwing.class

Next step, create the jar file. Each jar file have a manifest file, where attributes related to the executable file are.

This is the content of my manifest file.

$cat manifest.mf
Main-class: start.HelloWorldSwing

Just describe what the main class is ( the one with the public static void main method )

Once the manifest is ready, the jar executable is invoked.

It has many options, here I'm using -c -m -f ( -c to create jar, -m to specify the manifest file , -f = the file should be named.. ) and the folder I want to jar.

$jar -cmf manifest.mf hello.jar start

This creates the .jar file on the system

You can later just double click on that file and it will run as expected.

To create the .jar file in JCreator you just have to use "Tools" menu, create jar, but I'm not sure how the manifest goes there.

Here's a video I've found about: Create a Jar File in Jcreator.

I think you may proceed with the other links posted in this thread once you're familiar with this ".jar" approach.

You can also use jnlp ( Java Network Launcher Protocol ) too.