关于java打印 invalid flavor报错问题。

java action classpublic void printNew(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {

        PrintRequestAttributeSet pras = new HashPrintRequestAttributeSet();
      
        DocFlavor flavor = DocFlavor.INPUT_STREAM.TEXT_HTML_UTF_8;
        System.out.println("printNew 2");
     
        PrintService defaultService = PrintServiceLookup.lookupDefaultPrintService();
    

        if (defaultService != null)
        {
        
         try
            {
        
             DocPrintJob job = defaultService.createPrintJob();
                FileInputStream fis = new FileInputStream("hello.html");
                DocAttributeSet das = new HashDocAttributeSet();
                Doc doc = new SimpleDoc(fis, flavor, das);
                job.print(doc, pras);
            }
            catch(Exception e)
            {
             e.printStackTrace();
            }
        }
    }我使用的html文件<html>
<head>
<meta http-equiv="Content-Language" content="en-us">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>UNLOADING DOCUMENT</title>
</head>
<body>
<h1 align="center"><b><font color="#000080"><u>UNLOADING DOCUMENT</u></font></b></h1>
</body>
</html>
但是每次打印总是报错
[3/23/10 11:08:44:265 EDT] 00000082 SystemErr     R sun.print.PrintJobFlavorException: invalid flavor
[3/23/10 11:08:44:296 EDT] 00000082 SystemErr     R  at sun.print.Win32PrintJob.print(Win32PrintJob.java:346)
[3/23/10 11:08:44:296 EDT] 00000082 SystemErr     R  at com.knightedcs.wms.configuration.struts.actions.UpdateLngSettingAction.printNew(UpdateLngSettingAction.java:454)请大家帮忙看看什么原因吧，谢谢啦