In my JFreeChart timeseries plots I find the legends lines to thin to see the colour accurately. Another post [ jfreechart - change sample of colors in legend ] suggested overriding a renderer method as follows:

renderer = new XYLineAndShapeRenderer()
{
    private static final long serialVersionUID = 1L;
    public Shape lookupLegendShape(int series)
    {
        return new Rectangle(15, 15);
    }
};

this approach works fine until you do what I did

renderer.setSeriesShapesVisible(i, false);

Once I did that the legend reverts back to a line. Is there any way round this?