code: public static <E> void spElement(E[] buffer, long offset, E e) {
      UNSAFE.putObject(buffer, offset, e);
    }
docs: A plain store (no ordering/fences) of an element to a given offset
  
  @param buffer this.buffer
  @param offset computed via {@link UnsafeRefArrayAccess#calcElementOffset(long)}
  @param e an orderly kitty