What i need to know is the correctness of the following getters / setters. Are they completely thread-safe? If not, in which case are they not thread-safe? Any remarks about behaviour are welcome, thanks guys 🙂

The code is in java, but the logic applies to any language that supports CAS and objects.

private Object obj; private AtomicLong version = new AtomicLong(0); private AtomicBoolean isUpdating = new AtomicBoolean(false);  public Object get() {     long before = version.get();     while (true) {         Object obj = this.obj;          long after = version.get();         if (before == after && before % 2 == 0)             return obj;          before = after;     } }  public void set(Object obj) {     while (!isUpdating.compareAndSet(false, true)) {         //spin     }      version.getAndIncrement();     this.obj = obj;     version.getAndIncrement();      isUpdating.set(false); }