public void actionPerformed(ActionEvent event) {
   JGrid grid = (JGrid) event.getSource();
   if (!grid.hasFocus()) {
     CellEditor cellEditor = grid.getCurrentCellEditor();
     if ((cellEditor != null) && !cellEditor.stopCellEditing()) {
       return;
     }
     grid.requestFocus();
   }
   SelectionModel selectionModel = grid.getSelectionModel();
   Cell selectedCell = selectionModel.getSelectedCell();
   int row = selectedCell.getRow();
   int column = selectedCell.getColumn();
   grid.editCellAt(row, column, null);
   Component editorComponent = grid.getEditorComponent();
   if (editorComponent != null) {
     editorComponent.requestFocus();
   }
 }