void () { 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); }