Below is a fairly simple TableCellRenderer for displaying an enum as
an Icon.  That works fine. But I added a wrinkle, changing the
background colour depending on whether the row is selected.

No background colour changes happen, even though isSelected is true
when it should be. I wonder if I am missing something obvious.

package com.mindprod.vercheck;

import javax.swing.*;
import javax.swing.table.TableCellRenderer;
import java.awt.*;

/**
* render a the AppSate enum cell, use icon without text.
*/
final class AppStateRenderer implements TableCellRenderer
   {
   // ------------------------------ FIELDS
------------------------------

   private static final JLabel template = new JLabel( "",
JLabel.CENTER );

   private Color background;

   private Color selectedBackground;

   // -------------------------- PUBLIC INSTANCE  METHODS
--------------------------
   /**
    * constructor
    *
    * @param background         background colour
    * @param selectedBackground background colour when seleced
    */
   public AppStateRenderer( Color background, Color
selectedBackground )
       {
       this.background = background;
       this.selectedBackground = selectedBackground;
       }

   public Component getTableCellRendererComponent( JTable table,
                                                   Object value,
                                                   boolean
isSelected,
                                                   boolean hasFocus,
                                                   int row,
                                                   int column )
       {
       System.err.println( "selected:" + isSelected + " " + row + " "
+ table.getSelectedRow() );

       template.setIcon( ( (AppState) value ).getIcon() );
       template.setBackground( isSelected? selectedBackground :
background );
       
       return template;
       }
   }