一个奇怪的有关问题

一个奇怪的问题
我在学习用jfreechart画图，刚学到同时显示多个饼图，看到文档中有个例子，就自己试了一下，发现结果偏差很大，画出来的饼图还没标签大，应该怎么设置？

Java code

import org.jfree.chart.ChartFactory;import org.jfree.chart.ChartFrame;import org.jfree.chart.JFreeChart;import org.jfree.chart.labels.StandardPieSectionLabelGenerator;import org.jfree.chart.plot.MultiplePiePlot;import org.jfree.chart.plot.PiePlot;import org.jfree.data.category.CategoryDataset;import org.jfree.data.general.DatasetUtilities;import org.jfree.util.TableOrder;public class Second {    public static void main(String[] args) {        JFreeChart chart =createChart(createDataset());        ChartFrame frame = new ChartFrame("First", chart);        frame.pack();        frame.setVisible(true);    }    private static CategoryDataset createDataset() {        double[][] ds = { { 3.0, 4.0, 3.0, 5.0 }, { 5.0, 7.0, 6.0, 8.0 },                { 5.0, 7.0, Double.NaN, 3.0 }, { 1.0, 2.0, 3.0, 4.0 },                { 2.0, 3.0, 2.0, 3.0 } };        CategoryDataset categorydataset = DatasetUtilities                .createCategoryDataset("Region ", "Sales/Q", ds);        return categorydataset;    }    private static JFreeChart createChart(CategoryDataset categorydataset) {        JFreeChart jfreechart = ChartFactory.createMultiplePieChart(                "Multiple Pie Chart", categorydataset, TableOrder.BY_ROW, true,    true, false);                MultiplePiePlot multiplepieplot = (MultiplePiePlot) jfreechart.getPlot();        JFreeChart jfreechart_0_ = multiplepieplot.getPieChart();        PiePlot pieplot = (PiePlot) jfreechart_0_.getPlot();        pieplot.setLabelGenerator(new StandardPieSectionLabelGenerator("{0}"));        pieplot.setInteriorGap(0.3);        return jfreechart;    }}