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

import org.jfree.chart.ChartUtilities;
import java.io.File;
import java.io.IOException;

public class Test4_1{
  public static void main(String[] args) {
    DefaultPieDataset data = new DefaultPieDataset();
    data.setValue("支持する", 56);
    data.setValue("支持しない", 41);
    data.setValue("未回答", 3);

    JFreeChart chart = 
      ChartFactory.createPieChart("Title", data, false, false, false);

    File file = new File("./test4_1.png");
    try {
      ChartUtilities.saveChartAsPNG(file, chart, 300, 300);
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}