firePropertyChange(CELL_RENDERER_PROPERTY, oldRenderer, cellRenderer);
changeSupport.firePropertyChange(CELL_RENDERER_PROPERTY, oldRenderer, cellRenderer);
  public void setCellRenderer(TableCellRenderer renderer)  {    if (cellRenderer == renderer)      return;        TableCellRenderer oldRenderer = cellRenderer;    cellRenderer = renderer;    firePropertyChange(CELL_RENDERER_PROPERTY, 		       oldRenderer, cellRenderer);  }