private void handleInMoveMode(final MouseWheelEvent event) {
    final boolean scrollDirection = event.getUnitsToScroll() > 0;

    if (event.isAltDown()) {
      moveVertical(scrollDirection);
    } else {
      moveHorizontal(scrollDirection);
    }
  }
Listens to mouse wheel events in edit mode.
java/zylib/src/main/java/com/google/security/zynamics/zylib/yfileswrap/gui/zygraph/editmode/ZyEditModeMouseWheelListener.java