JSP引入JFreeChart

JFreeChart chart = JFreeChartTool.ToLineChart(list);
   try {
    HttpSession session = ServletActionContext.getRequest()
      .getSession();
    String filename = ServletUtilities.saveChartAsPNG(chart, 500,
      300, null, session);
    System.out.println(filename);
    String graphURL = request.getContextPath()
      + "/servlet/DisplayChart?filename=" + filename;
    request.setAttribute("graphURL2", graphURL);
   } catch (IOException e) {
    e.printStackTrace();
   }

页面中加入：

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