class MyImagePainter extends ImagePainter
{
   Image imageObject

   public void setImage(Image image)
   {
	this.imageObject= image;
   }

   @Override
   protected Image getImage(ILayerCell cell, IConfigRegistry configRegistry)
   {
	//return the currently saved image
	return imageObject;
   }	
 
// more methods if required.
......
........

}

MyAction implements IMouseAction
{ 
   MyImagePainter imagePainterObj;

   
   public void run(NatTable nattable, MouseEvent event)
   {
      // add your code logic and set image accordingly
     
      // For example
      //if(state)
        //imagePainterObj.setImage(checkedImage)
      //else
        //imagePainterObj.setImage(unCheckedImage)      
   }

// more methods if required.
......
........
}