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" .
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" .
But when I run "java -jar MyJar.jar ",I get an error :
Exception in thread "main" java.lang.NoClassDefFoundError: MyClass$1
at MyClass.main(MyClass.java:6) .And I don't understand why <the java tutorial> teach us by error.
I get the instruction from http://java.sun.com/docs/books/tutorial/javabeans/writingbean/index.html
the tittle is Writing a Simple Bean;
who can tell me how to write a simple bean and excute it in the beanbox ?
I will add score to you