Java 将 XChart 保存为 PDF

Question

使用XChart我可以制作漂亮的图表。当我制作图表时，我可以右键单击它，然后出现 "save as" 的选项。然后，我可以将图片以指定的格式保存到指定的目录下。

我如何编写 Java 代码来为我自动执行此操作？也就是说，我有一个创建大约五十张图表的应用程序，我不想每次运行应用程序时都必须手动将每个图表保存在它所属的位置。

这是我制作图表的方法：

private void makeLineChart(int[][] data, String title) {
    MyLineChart c = new MyLineChart(data, title);
    XYChart chart = c.getChart();
    new SwingWrapper<XYChart>(chart).displayChart();
    // save as pdf...?
}

Answer 1

xchart的示例代码有解决办法。 BitmapEncoder 可以在您每次启动应用程序时执行此操作。BitmapEncoder.saveBitmap(chart, "./Sample_Chart", BitmapFormat.PNG);

public class Example1 {

public static void main(String[] args) throws Exception {
 double[] yData = new double[] { 2.0, 1.0, 0.0 };
// Create Chart
XYChart chart = new XYChart(500, 400);
chart.setTitle("Sample Chart");
chart.setXAxisTitle("X");
chart.setXAxisTitle("Y");
XYSeries series = chart.addSeries("y(x)", null, yData);
series.setMarker(SeriesMarkers.CIRCLE);

BitmapEncoder.saveBitmap(chart, "./Sample_Chart", BitmapFormat.PNG);
BitmapEncoder.saveBitmap(chart, "./Sample_Chart", BitmapFormat.JPG);
BitmapEncoder.saveJPGWithQuality(chart, "./Sample_Chart_With_Quality.jpg", 0.95f);
BitmapEncoder.saveBitmap(chart, "./Sample_Chart", BitmapFormat.BMP);
BitmapEncoder.saveBitmap(chart, "./Sample_Chart", BitmapFormat.GIF);

BitmapEncoder.saveBitmapWithDPI(chart, "./Sample_Chart_300_DPI", BitmapFormat.PNG, 300);
BitmapEncoder.saveBitmapWithDPI(chart, "./Sample_Chart_300_DPI", BitmapFormat.JPG, 300);
BitmapEncoder.saveBitmapWithDPI(chart, "./Sample_Chart_300_DPI", BitmapFormat.GIF, 300);

VectorGraphicsEncoder.saveVectorGraphic(chart, "./Sample_Chart", VectorGraphicsFormat.EPS);
VectorGraphicsEncoder.saveVectorGraphic(chart, "./Sample_Chart", VectorGraphicsFormat.PDF);
VectorGraphicsEncoder.saveVectorGraphic(chart, "./Sample_Chart", VectorGraphicsFormat.SVG);

} }

Answer 2

类似于，但更具体地针对 OP 的问题，并且仅将输出写入 PDF。

可以使用 VectorGraphicsEncoder, which is shown in the examples under the heading "Save Chart as Bitmap".

编写 PDF

在这里，我将示例精简为仅包含相关信息：

package com.example;

import java.io.IOException;

import org.knowm.xchart.VectorGraphicsEncoder;
import org.knowm.xchart.VectorGraphicsEncoder.VectorGraphicsFormat;
import org.knowm.xchart.XYChart;
import org.knowm.xchart.XYSeries;
import org.knowm.xchart.style.markers.SeriesMarkers;

public class TryXchartToPdf extends XchartBase {
    /**
     * Creates a simple Chart and saves it as a PDF file.
     * @throws IOException
     */

    public static void main(String[] args) throws IOException {

        double[] yData = new double[] { 2.0, 1.0, 0.0 };

        // Create Chart
        XYChart chart = new XYChart(500, 400);
        chart.setTitle("Sample Chart");
        chart.setXAxisTitle("X");
        chart.setXAxisTitle("Y");
        XYSeries series = chart.addSeries("y(x)", null, yData);
        series.setMarker(SeriesMarkers.CIRCLE);

        VectorGraphicsEncoder.saveVectorGraphic(chart, "./Sample_Chart", VectorGraphicsFormat.PDF);

    }
}

Java 将 XChart 保存为 PDF

Java save XChart as a PDF

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