Make a JAR executable

In the manifest file of a JAR, it is possible to specify the class to be used when the JVM is lauched with the JAR as parameter. The class must have a main().

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); } }

Then create this manifest file (manifest.mft) with any text editor.

   Manifest-Version: 1.0
  Main-Class: MyClass
  Classpath: .\MyJar.jar

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

   jar cvfm MyJar.jar manifest.mft MyClass.class

Then you are able to start the MyClass.class by double-clicking on the MyJar.jar file (if the JRE is correctly installed) or by typing

   java -jar MyJar.jar

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

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

Then if you have the jar file MyJar.jar accessible via the PATH environment variable, typing "MyJar" on the DOS command line will invoke "java -jar MyJar.jar" .

For Details: Java Tips