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

import javax.swing.JFrame;
import java.awt.BorderLayout;
import org.jfree.chart.ChartPanel;

import java.awt.Color;
import java.awt.GradientPaint;

public class Test5_1 extends JFrame{
  public static void main(String[] args) {
    Test5_1 frame = new Test5_1();

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setBounds(10, 10, 500, 500);
    frame.setTitle("グラフサンプル");
    frame.setVisible(true);
  }

  Test5_1(){
    JFreeChart chart = 
      ChartFactory.createPieChart("昼食", createData(), false, false, false);

    GradientPaint gradient = new GradientPaint(
        50.0f, 50.0f, Color.ORANGE, 
        190.0f, 110.0f, Color.YELLOW
    );
    chart.setBackgroundPaint(gradient);

    ChartPanel cpanel = new ChartPanel(chart);
    getContentPane().add(cpanel, BorderLayout.CENTER);
  }

  private DefaultPieDataset createData(){
    DefaultPieDataset data = new DefaultPieDataset();
    data.setValue("外食", 37);
    data.setValue("弁当", 31);
    data.setValue("食べない", 32);

    return data;
  }
}