int row = table.getSelectedRow();
int column = table.getSelectedColumn();
table.setValueAt(null, row, column);
}
});
insertNullMenuItem.setEnabled(selectedRowCount == 1 && selectedColumnCount == 1 && table.convertColumnIndexToModel(table.getSelectedColumn()) != 0);
menu.add(insertNullMenuItem);
menu.addSeparator();
JMenuItem deleteRowMenuItem = new JMenuItem("Delete " + (selectedRowCount > 1? selectedRowCount + " rows": "row"));
deleteRowMenuItem.addActionListener(new ActionListener() {
@Override