private void listenForDocumentChanges() {
      Disposer.register(myEditor.getDisposable(), this);
      myEditor.getDocument().addDocumentListener(this, this);
      myEditor.getCaretModel().addCaretListener(this, this);
      myEditor.putUserData(SYNCHRONIZER_KEY, this);
      for (Caret caret : myEditor.getCaretModel().getAllCarets()) {
        Couple<RangeMarker> markers = getMarkers(caret);
        if (markers != null) {
          allMarkers.add(markers.first);
          allMarkers.add(markers.second);
        }
      }
    }
private void listenForDocumentChanges()