JFreeChart pie chart

In this example, we will create a pie chart using JFreeChart library.

JFreeChart is a popular Java library for creating charts. JFreeChart allows to create a wide variety of both interactive and non-interactive charts. We can create line charts, bar charts, area charts, scatter charts, pie charts, Gantt charts, and various specialized charts such as wind charts or bubble charts.

JFreeChart Maven dependency

For our projects, we use the below Maven dependency:

<dependency>
    <groupId>org.jfree</groupId>
    <artifactId>jfreechart</artifactId>
    <version>1.5.0</version>
</dependency>

JFreeChart pie chart

A pie chart is a circular chart that is divided into slices to illustrate numerical proportion. A pie chart is created with the ChartFactory.createPieChart() method in JFreeChart.

The example uses a pie chart to show the market share of web servers:

package com.java.library.jfreechart;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;

import javax.swing.BorderFactory;
import javax.swing.JFrame;
import java.awt.Color;
import java.awt.EventQueue;

public class PieChartExample extends JFrame {
	
	private static final long serialVersionUID = 1L;

	public PieChartExample() {

        initUI();
    }

    private void initUI() {

        DefaultPieDataset dataset = createDataset();

        JFreeChart chart = createChart(dataset);
        ChartPanel chartPanel = new ChartPanel(chart);
        chartPanel.setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
        chartPanel.setBackground(Color.white);
        add(chartPanel);

        pack();
        setTitle("Pie chart");
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    private DefaultPieDataset createDataset() {

        DefaultPieDataset dataset = new DefaultPieDataset();
        dataset.setValue("Apache", 52);
        dataset.setValue("Nginx", 31);
        dataset.setValue("IIS", 12);
        dataset.setValue("LiteSpeed", 2);
        dataset.setValue("Google server", 1);
        dataset.setValue("Others", 2);

        return dataset;
    }

    private JFreeChart createChart(DefaultPieDataset dataset) {

        JFreeChart pieChart = ChartFactory.createPieChart(
                "Web servers market share",
                dataset,
                false, true, false);

        return pieChart;
    }

    public static void main(String[] args) {

        EventQueue.invokeLater(() -> {

        	PieChartExample ex = new PieChartExample();
            ex.setVisible(true);
        });
    }
}

Output

Run above Java program will output: