private String getCellToolTip(MouseEvent event) {
        String toolTip = null;

        int col = columnAtPoint(event.getPoint());
        int row = rowAtPoint(event.getPoint());

        if (row >= 0 && col >= 0) {
            TableCellRenderer renderer = getCellRenderer(row, col);
            Component component = prepareRenderer(renderer, row, col);

            if (component instanceof JLabel) {
                // Convert the event to the renderer's coordinate system
                Rectangle cellRect = getCellRect(row, col, false);
                if(cellRect.width < component.getPreferredSize().width) {
                    toolTip = ((JLabel)component).getText();
                }
            }
        }
        return toolTip;
    }