Hi,
I has problem in drawing graph in servlet by using JFreeChart. Below is a part of my servlet program :
...
xyData = createXYDataSource2();
chart.setAntiAlias(false);
chart = JFreeChart.createTimeSeriesChart(xyData);
StandardTitle title = (StandardTitle)chart.getTitle();
title.setTitle("Value of GBP");
chart.setChartBackgroundPaint(new GradientPaint(0, 0, Color.red,0, 1000, Col
or.blue));
Plot myPlot = chart.getPlot();
Axis myVerticalAxis = myPlot.getAxis(Plot.VERTICAL_AXIS);
myVerticalAxis.setLabel("USD per GBP");
try {
frame = new Frame();
frame.addNotify();
Image image = frame.createImage(WIDTH, HEIGHT);
g = image.getGraphics();
chart.draw((Graphics2D)g,new Rectangle2D.Double(10, 10, 430,250));
res.setContentType("image/gif");
GifEncoder encoder = new GifEncoder(image, out);
encoder.encode();
...
GifEncoder is a class for encoding GIF image that I downloaded in Acme. My program can be compiled successfully. However when I run it, it will return a blank image. What's wrong ?
Please help since I am urgent in doing it. Thank you very much.
Stanley
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