如何以编程方式将ChartPanel中的当前图表保存为PNG?

解决办法是使用一种方法 ChartUtilities.writeChartAsPNG

例子:

try {

    OutputStream out = new FileOutputStream(chartName);
    ChartUtilities.writeChartAsPNG(out,
            aJFreeChart,
            aChartPanel.getWidth(),
            aChartPanel.getHeight());

} catch (IOException ex) {
    logger.error(ex);
}

此外,您还可以执行以下操作:

public static void exportAsPNG throws IOException {
    JFreeChart chart = createChart(createDataset());


    BufferedImage image = new BufferedImage(600, 400, BufferedImage.TYPE_INT_ARGB);
    Graphics2D g2 = image.createGraphics();

    g2.setRenderingHint(JFreeChart.KEY_SUPPRESS_SHADOW_GENERATION, true);
    Rectangle r = new Rectangle(0, 0, 600, 400);
    chart.draw(g2, r);
    File f = new File("/tmp/PNGTimeSeriesChartDemo1.png");



    BufferedImage chartImage = chart.createBufferedImage( 600, 400, null); 
    ImageIO.write( chartImage, "png", f ); 
}

1.5版之前使用 ChartUtilities 班

ChartUtilities.saveChartAsPNG(<File>, chart, width, height);
ChartUtilities.writeChartAsPNG(<OutputStream>, chart, width, height);

已重命名1.5版JFreeChart 图表实用程序 类到 ChartUtils 。它提供了相同的功能。

ChartUtils.saveChartAsPNG(<File>, chart, width, height);
ChartUtils.writeChartAsPNG(<OutputStream>, chart, width, height);

请注意,这些方法有更多变体。