calling a java method from javascript

Author: winterbe

res/nashorn1.js

@@ -1,4 +1,4 @@
 var fun = function(name) {
-    print('Hi there, ' + name);
-    return "success";
+    print('Hi there from Javascript, ' + name);
+    return "greetings from javascript";
 };

res/nashorn2.js

@@ -0,0 +1,3 @@
+var Nashorn2 = Java.type('com.winterbe.java8.Nashorn2');
+var result = Nashorn2.fun('John Doe');
+print('\n' + result);

src/com/winterbe/java8/Nashorn1.java

@@ -3,18 +3,17 @@
 import javax.script.Invocable;
 import javax.script.ScriptEngine;
 import javax.script.ScriptEngineManager;
-import javax.script.ScriptException;
-import java.io.FileNotFoundException;
 import java.io.FileReader;
 
 /**
+ * Calling javascript functions from java with nashorn.
+ *
  * @author Benjamin Winterberg
  */
 public class Nashorn1 {
 
-    public static void main(String[] args) throws ScriptException, FileNotFoundException, NoSuchMethodException {
-        ScriptEngine engine = new ScriptEngineManager()
-                .getEngineByName("nashorn");
+    public static void main(String[] args) throws Exception {
+        ScriptEngine engine = new ScriptEngineManager().getEngineByName("nashorn");
         engine.eval(new FileReader("res/nashorn1.js"));
 
         Invocable invocable = (Invocable) engine;

src/com/winterbe/java8/Nashorn2.java

@@ -0,0 +1,24 @@
+package com.winterbe.java8;
+
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import java.io.FileReader;
+
+/**
+ * Calling java methods from javascript with nashorn.
+ *
+ * @author Benjamin Winterberg
+ */
+public class Nashorn2 {
+
+    public static String fun(String name) {
+        System.out.format("Hi there from Java, %s", name);
+        return "greetings from java";
+    }
+
+    public static void main(String[] args) throws Exception {
+        ScriptEngine engine = new ScriptEngineManager().getEngineByName("nashorn");
+        engine.eval(new FileReader("res/nashorn2.js"));
+    }
+
+}