Question

I have this class:

public class Test {
    public static void main(String[] args) {
        System.out.println("Hello World!");
    }
}

And I used Eclipse’s “Export to runnable JAR” function to make it into a executable jar-file (test.jar). When I run this program in Eclipse, it prints out “Hello World!”, but when I call the jar-file from the command line, nothing happens.

I have tried calling the jar-file like this:

test.jar
test.jar -jar

There is no output whatsoever.

I have another program that also has a side effect (in addition to output to stdout) and while the side effect is being performed (which tells me the jar-file was definitely executed), again no output is given to the command line. I have also tried using stderr, but that makes no difference. Does anybody know how I can make this work?

Thanks!

Answer 1

You must run the JAR using

java -jar test.jar

(Your JRE’s bin folder must be added to PATH in order to get the command working from any location)

NOTE: I know you created the JAR using Eclipse but you might want to know how does an executable JAR works