如何使用servlet输出jfreechart产生的图形?
qiubo 2003-10-08 11:21:33 网上有一个代码为:
package lius.chart.demo;
import java.io.IOException;
import javax.servlet.*;
import javax.servlet.http.HttpServlet;
import org.jfree.data.*;
import org.jfree.chart.*;
/**
* 演示通过servlet直接输出图表
* @author Winter Lau
*/
public class ChartDemoServlet extends HttpServlet {
public void service(ServletRequest req, ServletResponse res)
throws ServletException, IOException
{
res.setContentType("image/jpeg");
DefaultPieDataset data = getDataSet();
JFreeChart chart = ChartFactory.createPie3DChart("水果产量图",
data,
true,
false,
false
);
ChartUtilities.writeChartAsJPEG(res.getOutputStream(),
100,chart,400,300,null);
}
/**
* 获取一个演示用的简单数据集对象
* @return
*/
private static DefaultPieDataset getDataSet() {
DefaultPieDataset dataset = new DefaultPieDataset();
dataset.setValue("苹果",100);
dataset.setValue("梨子",200);
dataset.setValue("葡萄",300);
dataset.setValue("香蕉",400);
dataset.setValue("荔枝",500);
return dataset;
}
}
如何利用jsp提取图象并且显示?