Java JFreeChart如何用密集点绘制虚线

我正在尝试绘制平滑曲线，在这些点靠近的地方（-4.0,0.01），（-4.1,02），等等。该图将有多条线，我想用虚线为每条曲线。我正在使用JFreeChart，并编写了一个自定义的XylineandShaperEnder来创建虚线。但是，破折号并不总是出现。似乎数据集中的点越靠近，我得到的破折号就越少。有人知道我如何使用靠得很近但仍然得到虚线的点吗？下面的代码演示了这个问题。所有这些行都应该有破折号。我认为这个问题与Java使用BasicStroke绘制线条的方式有关，但我不确定。感谢您的帮助

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.ui.ApplicationFrame;

import javax.swing.*;
import java.awt.*;

public class IccGraph extends ApplicationFrame {

public IccGraph(String title){
    super(title);
    JPanel chartPanel = createPanel();
    chartPanel.setPreferredSize(new Dimension(450, 400));
    setContentPane(chartPanel);
}

private double probability(double x, double b){
    double top = Math.exp(x-b);
    double prob = top/(1+top);
    return prob;
}

public XYSeriesCollection createData(){
    XYSeriesCollection dataset = new XYSeriesCollection();
    XYSeries series1 = new XYSeries("Wide Points");
    XYSeries series2 = new XYSeries("Close Points");
    XYSeries series3 = new XYSeries("Very Close Points");

    double maxValue = 4.0;
    double value = -4.0;
    double prob = 0.0;

    //create series where x-axis values use increments of .5
    //will produce graph with dashes as expected
    while(value<maxValue){
        prob = probability(value, -1.0);
        series1.add(value, prob);
        value += .5;
    }

    //create series where x-axis values use increments of .1
    //will produce line with some dashes
    value = -4.0;
    while(value<maxValue){
        prob = probability(value, 0.0);
        series2.add(value, prob);
        value += .1;
    }

    //create series where x-axis values use increments of .01
    //will produce straight lines in graph
    value = -4.0;
    while(value<maxValue){
        prob = probability(value, 1.0);
        series3.add(value, prob);
        value += .01;
    }

    dataset.addSeries(series1);
    dataset.addSeries(series2);
    dataset.addSeries(series3);

    return dataset;
}

public JPanel createPanel(){
    JFreeChart chart = createChart(createData());
    ChartPanel panel = new ChartPanel(chart);
    return panel;
}

public JFreeChart createChart(XYSeriesCollection dataset){
    JFreeChart chart = ChartFactory.createXYLineChart(
                "",            // chart title
                "Theta",       // x axis label
                "Probability", // y axis label
                dataset,       // data
                PlotOrientation.VERTICAL,
                true,          // include legend
                true,          // tooltips
                false          // urls
        );

    XYLineAndShapeRenderer renderer = new XYLineAndShapeRenderer(){
        @Override
        public Stroke getItemStroke(int row, int col){
            Stroke dash1 = new BasicStroke(1.0f,
                        BasicStroke.CAP_SQUARE,
                        BasicStroke.JOIN_MITER,
                        10.0f,
                        new float[] {5.0f,5.0f},
                        0.0f);
            return dash1;
        }
    };
    renderer.setBaseShapesFilled(false);
    renderer.setDrawOutlines(false);

    XYPlot plot = (XYPlot)chart.getPlot();
    plot.setRenderer(renderer);

    return chart;
}

public static void main(String[] args) {
    IccGraph graph = new IccGraph("Line Dash Problem");
    graph.pack();
    graph.setVisible(true);
}

import org.jfree.chart.ChartFactory；
导入org.jfree.chart.ChartPanel；
导入org.jfree.chart.JFreeChart；
导入org.jfree.chart.plot.PlotOrientation；
导入org.jfree.chart.plot.XYPlot；
导入org.jfree.chart.renderer.xy.XYLineAndShapeRenderer；
导入org.jfree.data.xy.XYSeries；
导入org.jfree.data.xy.XYSeriesCollection；
导入org.jfree.ui.ApplicationFrame；
导入javax.swing.*；
导入java.awt.*；
公共类IccGraph扩展了ApplicationFrame{
公共IccGraph（字符串标题）{
超级（标题）；
JPanel chartPanel=createPanel（）；
chartPanel.setPreferredSize（新尺寸（450400））；
setContentPane（图表面板）；
}
私有双概率（双x，双b）{
双头=数学表达式（x-b）；
双探头=顶部/（1+顶部）；
返回问题；
}
公共XYSeriesCollection createData（）{
XYSeriesCollection数据集=新的XYSeriesCollection（）；
XYSeries系列1=新XYSeries（“宽点”）；
XYSeries系列2=新的XYSeries（“闭合点”）；
XYSeries系列3=新XYSeries（“非常接近点”）；
双最大值=4.0；
双值=-4.0；
双探针=0.0；
//创建x轴值使用0.5增量的系列
//将按预期生成带破折号的图形
虽然（valueOK），但我找到了答案。解决方案是使用renderer.setDrawSeriesLineAsPath（true）。下面列出的修订代码根据需要绘制三条虚线

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.ui.ApplicationFrame;

import javax.swing.*;
import java.awt.*;

public class IccGraph extends ApplicationFrame {

public IccGraph(String title){
    super(title);
    JPanel chartPanel = createPanel();
    chartPanel.setPreferredSize(new Dimension(450, 400));
    setContentPane(chartPanel);

}

private double probability(double x, double b){
    double top = Math.exp(x-b);
    double prob = top/(1+top);
    return prob;
}

public XYSeriesCollection createData(){
    XYSeriesCollection dataset = new XYSeriesCollection();
    XYSeries series1 = new XYSeries("Wide Points");
    XYSeries series2 = new XYSeries("Close Points");
    XYSeries series3 = new XYSeries("Very Close Points");

    double maxValue = 4.0;
    double value = -4.0;
    double prob = 0.0;

    //create series where x-axis values use increments of .5
    //will produce graph with dashes as expected
    while(value<maxValue){
        prob = probability(value, -1.0);
        series1.add(value, prob);
        value += .5;
    }

    //create series where x-axis values use increments of .1
    //will produce line with some dashes
    value = -4.0;
    while(value<maxValue){
        prob = probability(value, 0.0);
        series2.add(value, prob);
        value += .1;
    }

    //create series where x-axis values use increments of .01
    //will produce straight lines in graph
    value = -4.0;
    while(value<maxValue){
        prob = probability(value, 1.0);
        series3.add(value, prob);
        value += .01;
    }

    dataset.addSeries(series1);
    dataset.addSeries(series2);
    dataset.addSeries(series3);

    return dataset;
}

public JPanel createPanel(){
    JFreeChart chart = createChart(createData());
    ChartPanel panel = new ChartPanel(chart);
    return panel;
}

public JFreeChart createChart(XYSeriesCollection dataset){
    JFreeChart chart = ChartFactory.createXYLineChart(
                "",            // chart title
                "Theta",       // x axis label
                "Probability", // y axis label
                dataset,       // data
                PlotOrientation.VERTICAL,
                true,          // include legend
                true,          // tooltips
                false          // urls
        );

    XYLineAndShapeRenderer renderer = new XYLineAndShapeRenderer(){
        @Override
        public Stroke getItemStroke(int row, int col){
            Stroke dash1 = new BasicStroke(1.0f,
                        BasicStroke.CAP_SQUARE,
                        BasicStroke.JOIN_MITER,
                        10.0f,
                        new float[] {10.0f,5.0f},
                        0.0f);
            return dash1;
        }
    };
    renderer.setBaseShapesFilled(false);
    renderer.setDrawOutlines(false);
    renderer.setDrawSeriesLineAsPath(true);//this line is the solution

    XYPlot plot = (XYPlot)chart.getPlot();
    plot.setRenderer(renderer);

    return chart;
}

public static void main(String[] args) {
    IccGraph graph = new IccGraph("Line Dash Problem");
    graph.pack();
    graph.setVisible(true);
}


}

import org.jfree.chart.ChartFactory；
导入org.jfree.chart.ChartPanel；
导入org.jfree.chart.JFreeChart；
导入org.jfree.chart.plot.PlotOrientation；
导入org.jfree.chart.plot.XYPlot；
导入org.jfree.chart.renderer.xy.XYLineAndShapeRenderer；
导入org.jfree.data.xy.XYSeries；
导入org.jfree.data.xy.XYSeriesCollection；
导入org.jfree.ui.ApplicationFrame；
导入javax.swing.*；
导入java.awt.*；
公共类IccGraph扩展了ApplicationFrame{
公共IccGraph（字符串标题）{
超级（标题）；
JPanel chartPanel=createPanel（）；
chartPanel.setPreferredSize（新尺寸（450400））；
setContentPane（图表面板）；
}
私有双概率（双x，双b）{
双头=数学表达式（x-b）；
双探头=顶部/（1+顶部）；
返回问题；
}
公共XYSeriesCollection createData（）{
XYSeriesCollection数据集=新的XYSeriesCollection（）；
XYSeries系列1=新XYSeries（“宽点”）；
XYSeries系列2=新的XYSeries（“闭合点”）；
XYSeries系列3=新XYSeries（“非常接近点”）；
双最大值=4.0；
双值=-4.0；
双探针=0.0；
//创建x轴值使用0.5增量的系列
//将按预期生成带破折号的图形
while（值）