how to change pie chart colors of JFreeChart?

Question

how to customize the colors of JFreeChart graphic. lets see my java code :

private StreamedContent chartImage ;

public void init(){
    JFreeChart jfreechart = ChartFactory.createPieChart("title", createDataset(), true, true, false);
    File chartFile = new File("dynamichart");
    ChartUtilities.saveChartAsPNG(chartFile, jfreechart, 375, 300);
    chartImage = new DefaultStreamedContent(new FileInputStream( chartFile), "image/png");
}

public PieDataset createDataset() {
    DefaultPieDataset dataset = new DefaultPieDataset();
          dataset.setValue("J-2", 10);
          dataset.setValue("J-1", 15);
          dataset.setValue("J", 50);
          dataset.setValue("J+1", 20);
          dataset.setValue("J+2", 15);
    return dataset;
}

html page :

<p:graphicImage id="MyImage" value="#{beanCreateImage.chartImage}" />

Answer 1

You can change the color of single pieces like this:

JFreeChart chart = ChartFactory.createPieChart("title", createDataset(), true, true, false);
PiePlot plot = (PiePlot) chart.getPlot();
plot.setSectionPaint("J+1", Color.black);
plot.setSectionPaint("J-1", new Color(120, 0, 120));
// or do this, if you are using an older version of JFreeChart:
//plot.setSectionPaint(1, Color.black);
//plot.setSectionPaint(3, new Color(120, 0, 120));

So with your code, all the pies are colored automatically, after my code changes, the J-1 and J+1 have a fixed color, the rest gets automatically colored.