How to Display Values on the XY Line JFreeChart

Question:

I created a report with XYLine JFreeChart. It works fine but I want to display the values on each points on the lines. How to achieve my requirements?

Answer:

A chart customizer should be created to achieve the requirements:

http://jasperreports.sourceforge.net/sample.reference/charts/index.html#chartcustomizers

Please find below sample Java code to enable XYLine chart labels:

//import java.awt.Color;

import net.sf.jasperreports.engine.JRChart;
import net.sf.jasperreports.engine.fill.JRFillChart;
import net.sf.jasperreports.engine.fill.JRBaseFiller;
import net.sf.jasperreports.engine.fill.JRFillChartDataset;
import net.sf.jasperreports.engine.JRAbstractChartCustomizer;

import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.chart.labels.XYItemLabelGenerator;
import org.jfree.chart.JFreeChart;

public class XYChartCustomizer extends JRAbstractChartCustomizer
{
    private JRFillChart fillChart;
   
    @Override
    public void init(JRBaseFiller chartFiller, JRFillChart chart)
    {
        super.init(chartFiller, chart);
        this.fillChart = chart;
    }

    @Override
    public void customize(JFreeChart chart, JRChart jasperChart)
    {
        XYItemRenderer renderer = chart.getXYPlot().getRenderer();
        renderer.setBaseItemLabelsVisible(true);
        renderer.setBaseItemLabelGenerator((XYItemLabelGenerator) ((JRFillChartDataset) fillChart.getDataset()).getLabelGenerator());
    }

}

In order to use this XYLine chart customizer, compile the code to a class, deploy it in the application class path, then reference it in the chart:

            <xyLineChart>
                <chart evaluationTime="Report" customizerClass="XYChartCustomizer">
                    <reportElement x="0" y="0" width="800" height="550" uuid="6db96f94-44ed-4847-a505-6dda967fe299"/>
                    <chartTitle/>

                ...
            </xyLineChart>

Printscreen of applying the customizer:

Ref. Case #00063995