Make a JAR executableTag(s): Environment

Try with this simple class

import java.awt.*;
import java.awt.event.*;

public class MyClass {
 public static void main(String[] args) {
    Frame f = new Frame();
    f.addWindowListener
          (new WindowAdapter() {
              public void windowClosing(WindowEvent e) {
                 System.exit(0);
                 }
              }
    );
    f.add(new Label("Hello world"));
    f.setSize(200,200);
    f.setVisible(true);
 }
}

Manifest-Version: 1.0
Main-Class: MyClass
Class-path: .

The Class-path is used to specify the dependency of this jar (if any). You add the directories and jars separated by a space. It is important because when running a jar , the CLASSPATH definition (as defined by the environnement variable) is overridden.

Next, you include the manifest file in the JAR (MyJar.jar) with the MyClass class.

jar cvfm myjar.jar manifest.mft *.class

java -jar myjar.jar

You can verify that everything is ok with the following command from a DOS Shell

>assoc .jar
.jar=jarfile

>ftype jarfile
jarfile="C:\Program Files\Java\jre1.5.0_10\bin\javaw.exe" -jar "%1" %*

If the association is broken or you need to change the JRE used then by using the assoc/ftype utilities, you can modify the association easily (use /? to display the syntax of the assoc and ftype utilities).

NOTE: On WinXp (or better), your user account needs to be at the Admin level.

On Windows (NT or better), you can also make JARs run from the command-line by setting the PATHEXT environment variable, for example

SET PATHEXT=.EXE;.BAT;.CMD;.JAR