JFreeChart-FX时间序列图垂直刻度标签重叠域轴及缩放异常问题求助

该异常是jfreechart-fx适配JavaFX渲染层时的边界计算缺陷导致：垂直刻度标签的宽高计算未与JavaFX的坐标映射逻辑对齐，仅在FX渲染环境下触发，Swing/原生Java2D渲染逻辑不受影响。窗口缩放时框架会自动重新计算刻度间隔，标签长度变化进一步加重了重叠现象。

可任选以下一种或组合使用解决重叠问题：

• 调整域轴刻度标签内边距，给垂直方向预留足够展示空间，在设置垂直刻度标签的代码后新增：

  domainAxis.setTickLabelInsets(new Insets(25, 2, 2, 2));
  

  需导入java.awt.Insets包，可根据标签长度调整第一个参数（顶部内边距）的数值。
• 固定域轴刻度间隔，避免窗口缩放时自动调整刻度导致的标签位移：

  domainAxis.setTickUnit(new DateTickUnit(DateTickUnitType.DAY, 1));
  

  需导入org.jfree.chart.axis.DateTickUnit、org.jfree.chart.axis.DateTickUnitType包，可根据数据的时间跨度调整刻度单位和间隔。
• 调整绘图区与坐标轴的偏移量，给底部域轴预留更多展示空间：

  xyplot.setAxisOffset(new RectangleInsets(5, 5, 35, 5));
  

  RectangleInsets的四个参数分别对应上、左、下、右的偏移量，增大第三个参数（底部偏移值）即可给垂直标签预留足够位置，需导入org.jfree.ui.RectangleInsets包。

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Insets;
import java.text.NumberFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.stage.Stage;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.axis.DateTickUnit;
import org.jfree.chart.axis.DateTickUnitType;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.fx.ChartViewer;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYSplineRenderer;
import org.jfree.data.time.Day;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.ui.RectangleInsets;

public class SplineTest extends Application {

    @Override
    public void start(Stage stage) throws ParseException {
        SimpleDateFormat inFormat = new SimpleDateFormat("yyyy-MM-dd");
        SimpleDateFormat outFormat = new SimpleDateFormat("dd-MM-yyyy");
        // 构造测试数据
        double[] values = new double[]{0.67, 0.67, 0.69, 0.70, 0.70, 0.71, 0.71};
        String[] dates = new String[]{"2021-11-09", "2021-11-10", "2021-11-11",
            "2021-11-12", "2021-11-15", "2021-11-16", "2021-11-17"};
        TimeSeries series = new TimeSeries("Time Series");
        for (int i = 0; i < values.length; i++) {
            Date date = inFormat.parse(dates[i]);
            series.add(new Day(date), values[i]);
        }
        TimeSeriesCollection dataset = new TimeSeriesCollection(series);
        // 配置值域轴
        NumberAxis rangeAxis = new NumberAxis("Value");
        NumberFormat numberFormat = NumberFormat.getInstance();
        numberFormat.setMinimumFractionDigits(2);
        numberFormat.setMaximumFractionDigits(2);
        rangeAxis.setNumberFormatOverride(numberFormat);
        rangeAxis.setLowerMargin(0.08);
        rangeAxis.setAutoRangeIncludesZero(false);
        // 配置定义域轴
        DateAxis domainAxis = new DateAxis("Date");
        domainAxis.setDateFormatOverride(outFormat);
        domainAxis.setVerticalTickLabels(true);
        // 新增修复代码
        domainAxis.setTickLabelInsets(new Insets(25, 2, 2, 2));
        domainAxis.setTickUnit(new DateTickUnit(DateTickUnitType.DAY, 1));
        // 配置渲染器和绘图区
        XYSplineRenderer r = new XYSplineRenderer(15);
        XYPlot xyplot = new XYPlot(dataset, domainAxis, rangeAxis, r);
        // 新增绘图区偏移配置
        xyplot.setAxisOffset(new RectangleInsets(5, 5, 35, 5));
        JFreeChart chart = new JFreeChart(null, xyplot);
        r.setSeriesPaint(0, new Color(255, 152, 0));
        r.setSeriesStroke(0, new BasicStroke(2.0f));
        // 渲染展示
        Scene scene = new Scene(new ChartViewer(chart));
        stage.setTitle("SplineTest");
        stage.setScene(scene);
        stage.setWidth(600);
        stage.setHeight(400);
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

内容的提问来源于stack exchange，提问作者trashgod