eleinadani

// Create the JS runtime (aka, "Context")
Context cx = Context.create("js");
Value json = cx.eval("js", "(function(x,y) { return JSON.stringify({x:x,y:y}); })");
// Use the function
json.execute(42,43).asString();

eleinadani

Thread thread = new Thread(new Runnable() {
  @Override
  public void run() {
    while (true) {
      json.execute(42,43).asString();
    }
  }
});
thread.start();
while (true) {

eleinadani

const Thread = Java.type('java.lang.Thread')
// `function run()` is converted to a Java Runnable instance by GraalVM
const t = new Thread(function run() {
    // this will never be executed, as an exception will be thrown
    console.log('hello from another thread!')
});
// creating a thread does not imply concurrent access to a shared JS object.
// starting the thread, however, will result in a concurrent access to the
// shared Runnable object (that is, the JavaScript 'run' function above).
t.start();

eleinadani

Context c1 = Context.create("js");
Context c2 = Context.create("js");
String jsCode = "(function(x,y) { return JSON.stringify({x:x,y:y}); })";

Value json1 = c1.eval("js", jsCode);
Value json2 = c2.eval("js", jsCode);

Thread thread = new Thread(new Runnable() {
  @Override
  public void run() {

eleinadani

Context cx = Context.create("js");
Value jsCode = cx.eval("js", "(function(x,y) { return JSON.stringify({x:x,y:y}); })");

Thread thread = new Thread(new Runnable() {
  @Override
  public void run() {
    while (true) {
      synchronized (cx) {
        jsCode.execute(42,43).asString();
      }

eleinadani

Context c1 = Context.create("js");
Context c2 = Context.create("js");

// create and share a thread-safe counter
AtomicInteger counter = new AtomicInteger(0);
c1.getBindings("js").putMember("counter", counter);
c2.getBindings("js").putMember("counter", counter);

Thread thread = new Thread(new Runnable() {
  @Override

eleinadani

let w = new Worker(`
        const JavaClass = Java.type('my.very.important.JavaClass');
        const { parentPort } = require('worker_threads');
        parentPort.postMessage(JavaClass.someVeryLongCall());
    `, {eval:true});

w.on('message', (m) => {
  console.log('Got data from Java, via worker thread:' + m);
});

eleinadani

let w = new Worker(`
        const { parentPort } = require('worker_threads');
        parentPort.on('message', (m) => {
          const x = m.random.nextInt(100);
          const y = m.random.nextInt(100);
          var Point = Java.type('java.awt.Point');
          parentPort.postMessage(new Point(x,y));
        });
`, {eval:true});

eleinadani

function JavaToJSNotifier {
  this.queue = new java.util.concurrent.LinkedBlockingDeque();
  this.worker = new Worker(`
      const { workerData, parentPort } = require('worker_threads');
      while (true) {
        // block the worker waiting for the next notification from Java
        var data = workerData.queue.take();
        // notify the main event loop that we got new data 
        parentPort.postMessage(data);
      }`,

eleinadani

public class AwesomeClass {
  // a concurrent queue shared with Node
  private final Queue<Object> queue;
  
  public AwesomeClass(Queue<Object> queue) {
    this.queue = queue;
  }
  
  public void start() {
    Thread thread = new Thread(new Runnable() {