update README (#237)

examples/functions/Java/func.java

@@ -0,0 +1,11 @@
+package fx;
+
+import org.json.JSONObject;
+
+public class Fx {
+    public int handle(JSONObject input) {
+        String a = input.get("a").toString();
+        String b = input.get("b").toString();
+        return Integer.parseInt(a) + Integer.parseInt(b);
+    }
+}