int (int direction) { JViewport viewport = getViewport(); if (viewport != null) { Scrollable scrollable = getScrollableViewToCalculateIncrement(viewport.getView()); if (scrollable != null) return scrollable.getScrollableBlockIncrement(viewport.getViewRect(), orientation, direction); if (!isBlockIncrementSet) { Dimension size = viewport.getExtentSize(); return orientation == HORIZONTAL ? size.width : size.height; } } return super.getBlockIncrement(direction); }