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Tim Rohaly

Just like with executing a program just use the the -D flag along with the -jar flag. Here is my test case:

public class property {
    public static void main(String[] args) {
        System.out.println("User-defined property = " +
                           System.getProperty("my.property"));
    }
}

Compile and run using

    java -Dmy.property=test property

and you'll get the results:

    User-defined property = test

Now create a manifest (call it manifest.mf) that contains only the line:

    Main-Class: property

as the first line, then jar up property.class with this manifest:

    jar cvfm property.jar manifest.mf property.class

Now try to run as an executable jar:

    java -Dmy.property=test -jar property.jar

and you'll get the same result.

Warning:Be sure the last line of the manifest file has a newline at the end.