adding main class into the manifest file

I created a jar file like this :

jar cf myJAR.jar *.class

But this thing is not executable because the mainfest file does not know in which .class file is 开发者_StackOverflow社区the main file ?

Now how can i set the main class into the manifest file ?

The manifest file must include the following line

Main-Class: MyPackage.MyClass

In JDK6 there is a commandline parameter to add it automatically

jar cfe Main.jar foo.Main foo/Main.class

foo is the package in this example. The second example creates the manifest automatically.