Question

Given the following class:

public class SpecifySystemPropertiesCommandLine {

    public static void main(String[] args) {
        String prop1 = System.getProperty("prop1", "defaultvalue");
        String prop2 = System.getProperty("prop2", "defaultvalue");

        System.out.println("prop1 = " + prop1);
        System.out.println("prop2 = " + prop2);
    }

}

Why does the following not work:

$ java -jar sysprop.jar -Dprop1="i can haz?"
prop1 = defaultvalue
prop2 = defaultvalue

but this works:

$ java -Dprop1="i can haz?" -jar sysprop.jar 
prop1 = i can haz?
prop2 = defaultvalue

Answer 1

See http://docs.oracle.com/javase/6/docs/technotes/tools/windows/java.html.

Everything after the jar file name is an argument passed to the main method of your class/app.

-Dprop=val is an argument that is passed to the java process.