Java8 JS Nashorn convert array to Java array

javascript arrays scala nashorn
user2053898 picture user2053898 · Mar 18, 2014 · Viewed 17.1k times · Source

How can I convert JS array to native array ? In Rhino conversion looked like (Scala code):

val eng = (new javax.script.ScriptEngineManager).getEngineByName("JavaScript")
val obj = eng.eval("[1,2,3,4]")
val arr = obj.asInstanceOf[sun.org.mozilla.javascript.internal.NativeArray]

In Nashorn NativeArray absent, and I can't find any documentation on conversion.

Answer

Attila Szegedi picture Attila Szegedi · Mar 19, 2014

From Java (and Scala), you can also invoke convert method on jdk.nashorn.api.scripting.ScriptUtils class. E.g. from Java:

import jdk.nashorn.api.scripting.ScriptUtils;
...
int[] iarr = (int[])ScriptUtils.convert(arr, int[].class)

my Scala is not too fluent, but I believe the equivalent is:

val iarr = ScriptUtils.convert(arr, Array[Int]).asInstanceOf(Array[Int])

Related questions

How can I remove a specific item from an array?

I have an array of numbers and I'm using the .push() method to add elements to it. Is there a simple way to remove a specific element from an array? I'm looking for the equivalent of something like: array.remove(…

Read More
For-each over an array in JavaScript

How can I loop through all the entries in an array using JavaScript? I thought it was something like this: forEach(instance in theArray) Where theArray is my array, but this seems to be incorrect.

Read More
Loop through an array in JavaScript

In Java you can use a for loop to traverse objects in an array as follows: String[] myStringArray = {"Hello", "World"}; for (String s : myStringArray) { // Do something } Can you do the same in JavaScript?

Read More