Java 类org.jfree.chart.servlet.ServletUtilities 实例源码

protected String createAndSaveImage(DesignOptions options, JFreeChart chart, ChartRenderingInfo renderingInfo) throws GeneratorException {
    int width = options.getWidth();
    int height = options.getHeight();
    BufferedImage image = chart.createBufferedImage(width, height, renderingInfo);
    Graphics2D chartGraphics = image.createGraphics();
    chartGraphics.setColor(Color.white);
    chartGraphics.fillRect(0, 0, width, height);
    chart.draw(chartGraphics, new Rectangle2D.Float(0, 0, width, height));

    try {
        return ServletUtilities.saveChartAsPNG(chart, width, height, renderingInfo, null);
    }
    catch (IOException e) {
        throw new GeneratorException("Could not save PNG!", e);
    }
}

@GET
@Path("/charts")
@Produces("image/png")
@ApiOperation(value = "", notes = "")
@ApiResponses(value = {
        @ApiResponse(code = 500, message = "Internal Server Error")
})
public Response doGetChart(@Context HttpSession session) throws IOException {

    DefaultPieDataset dataset = new DefaultPieDataset();
    dataset.setValue("Linux", 29);
    dataset.setValue("Mac", 20);
    dataset.setValue("Windows", 51);

    JFreeChart chart = ChartFactory.createPieChart3D("hello world",          // chart title
            dataset,                // data
            true,                   // include legend
            true,
            false);

    PiePlot3D plot = (PiePlot3D) chart.getPlot();
    plot.setStartAngle(290);
    plot.setDirection(Rotation.CLOCKWISE);
    plot.setForegroundAlpha(0.5f);

    //  Write the chart image to the temporary directory
    ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
    String filename = ServletUtilities.saveChartAsPNG(chart, 500, 300, info, session);

    byte[] imageData = FileUtils.readFileToByteArray(new File("/tmp/" + filename));

    //BufferedImage image = ...;

    /*ByteArrayOutputStream baos = new ByteArrayOutputStream();
    ImageIO.write(image, "png", baos);
    byte[] imageData = baos.toByteArray();*/

    // uncomment line below to send non-streamed
    // return Response.ok(imageData).build();

    // uncomment line below to send streamed
    return Response.ok(new ByteArrayInputStream(imageData)).build();
}