code: private void readObject(java.io.ObjectInputStream s)
        throws java.io.IOException, ClassNotFoundException {
      s.defaultReadObject();
  
      // Read in array length and allocate array
      int length = s.readInt();
      this.longs = new AtomicLongArray(length);
  
      // Read in all elements in the proper order.
      for (int i = 0; i < length; i++) {
        set(i, s.readDouble());
      }
    }
docs: Reconstitutes the instance from a stream (that is, deserializes it).