Invoking Javascript Functions from Java With Parameters

Create demo2.js file

var fn1 = function(fullName) {
	print('Hello ' + fullName);
}

var fn2 = function(a, b) {
	print('Sum: ' + (a + b));
}

Invoking Javascript Functions from Java With Parameters

package pmk.learnjava8withrealapps.nashorn;

import java.io.FileReader;
import javax.script.Invocable;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;

public class Demo2 {

	public static void main(String[] args) {

		try {
			ScriptEngine se = new ScriptEngineManager()
					.getEngineByName("nashorn");

			se.eval(new FileReader("src\\pmk\\learnjava8withrealapps\\nashorn\\demo2.js"));

			Invocable i1 = (Invocable)se;

			i1.invokeFunction("fn1", "Kevin");

			Invocable i2 = (Invocable)se;

			i2.invokeFunction("fn2", 1, 2);

		} catch (Exception e) {
			System.out.println(e.getMessage());
		}

	}

}

Output

Hello Kevin
Sum: 3