private void setRootColumnSize() {
    TableColumn column = getRootColumn();

    RootCellRenderer rootCellRenderer = (RootCellRenderer)column.getCellRenderer();
    rootCellRenderer.updateInsets();

    int rootWidth = rootCellRenderer.getColumnWidth();
    // NB: all further instructions and their order are important, otherwise the minimum size which is less than 15 won't be applied
    column.setMinWidth(rootWidth);
    column.setMaxWidth(rootWidth);
    column.setPreferredWidth(rootWidth);
  }
private void setRootColumnSize()