struts2 下载问题

<param name="inputName">inputStream</param>

我后台的方法getDownloadFile()

框架返回的是个 inputStream 流，你返回getDownloadFile 是个流吗？

public InputStream getDownloadFile() throws FileNotFoundException, UnsupportedEncodingException{
       fileN=new String(fileName.getBytes( "ISO8859-1" ), "utf-8" );
       File file = new File("D:\\xmxmmyeclipe6.5\\Gjdw_admin\\WebRoot\\"+DOWNLOADFILEPATH+fileN);
           System.out.println("dddddddddddddddddddddd"+DOWNLOADFILEPATH+fileN);
           InputStream is = new FileInputStream(file);
                                            InputStream is = new FileInputStream(file);
               return is;
          }     返回的是流

<param name="inputName">downloadFile</param>   public InputStream getDownloadFile() throws Exception
    {

           return ServletActionContext.getServletContext().getResourceAsStream(xxxx.jpg") ;

    }

//      public InputStream getDownloadFile() throws UnsupportedEncodingException {
//      fileN=new String(fileName.getBytes( "ISO8859-1" ), "utf-8" );
//     System.out.print( ServletActionContext.getServletContext().getResourceAsStream(DOWNLOADFILEPATH+fileN)+"/////////////大家后才是真的");
//          return
// ServletActionContext.getServletContext().getResourceAsStream(DOWNLOADFILEPATH+fileN);
//      }我一开始写过  没用  的    这样也不行

报的错就是 Can not find a java.io.InputStream with the name [downloadFile] 没有流信息，你debug 测试，看看是否跑到你返回流的那句代码。

<action name="download" class="com.tzht.uploadmesAction.DownloadAction">
            
            <param name="fileName"></param>
            <result name="success" type="stream">  这个是不是写在  result 中？

<result name="success" type="stream">
                 
                 <param name="contentType">
                     application/octet-stream
                 </param>
                 
                 <param name="contentDisposition">
                     attachment;filename="${downloadChineseFileName}"
                 </param>
                 
                 <param name="inputName">downloadFile</param>
                  <param name="bufferSize">4096</param>
                   <param name="contentLentgth">4096</param>
             </result>  他们已经在一个大result中了呀

/**
     * @see org.apache.struts2.dispatcher.StrutsResultSupport#doExecute(java.lang.String, com.opensymphony.xwork2.ActionInvocation)
     */
    protected void doExecute(String finalLocation, ActionInvocation invocation) throws Exception {        // Override any parameters using values on the stack
        resolveParamsFromStack(invocation.getStack(), invocation);        OutputStream oOutput = null;        try {
            if (inputStream == null) {
                // Find the inputstream from the invocation variable stack
                inputStream = (InputStream) invocation.getStack().findValue(conditionalParse(inputName, invocation));
            }       if (inputStream == null) {
                String msg = ("Can not find a java.io.InputStream with the name [" + inputName + "] in the invocation stack. " +
                    "Check the <param name=\"inputName\"> tag specified for this action.");
                LOG.error(msg);
                throw new IllegalArgumentException(msg);
            }            // Find the Response in context
            HttpServletResponse oResponse = (HttpServletResponse) invocation.getInvocationContext().get(HTTP_RESPONSE);            // Set the content type
            if (contentCharSet != null && ! contentCharSet.equals("")) {
                oResponse.setContentType(conditionalParse(contentType, invocation)+";charset="+contentCharSet);
            }
            else {
                oResponse.setContentType(conditionalParse(contentType, invocation));
            }            // Set the content length
            if (contentLength != null) {
                String _contentLength = conditionalParse(contentLength, invocation);
                int _contentLengthAsInt = -1;
                try {
                    _contentLengthAsInt = Integer.parseInt(_contentLength);
                    if (_contentLengthAsInt >= 0) {
                        oResponse.setContentLength(_contentLengthAsInt);
                    }
                }
                catch(NumberFormatException e) {
                    LOG.warn("failed to recongnize "+_contentLength+" as a number, contentLength header will not be set", e);
                }
            }            // Set the content-disposition
            if (contentDisposition != null) {
                oResponse.addHeader("Content-Disposition", conditionalParse(contentDisposition, invocation));
            }            // Set the cache control headers if neccessary
            if (!allowCaching) {
                oResponse.addHeader("Pragma", "no-cache");
                oResponse.addHeader("Cache-Control", "no-cache");
            }            // Get the outputstream
            oOutput = oResponse.getOutputStream();            if (LOG.isDebugEnabled()) {
                LOG.debug("Streaming result [" + inputName + "] type=[" + contentType + "] length=[" + contentLength +
                    "] content-disposition=[" + contentDisposition + "] charset=[" + contentCharSet + "]");
            }            // Copy input to output
            LOG.debug("Streaming to output buffer +++ START +++");
            byte[] oBuff = new byte[bufferSize];
            int iSize;
            while (-1 != (iSize = inputStream.read(oBuff))) {
                oOutput.write(oBuff, 0, iSize);
            }
            LOG.debug("Streaming to output buffer +++ END +++");            // Flush
            oOutput.flush();
        }
        finally {
            if (inputStream != null) inputStream.close();
            if (oOutput != null) oOutput.close();
        }
    }

奥我明白了但是我debug确实有对象呀java.io.FileInputStream@1ddc3ea没法传图请问有何见解呀

连接1
连接2
现在就是你的流没返回，contentLength 这个是返回的需要配吗。

本来我没配在网上查的加上了不好试没去还有好像txt的文件可以下载 word，exel好行就不能真怪

就报这个别的没有了严重 Can not find a java.io.InputStream with the name [downloadFile] in the invocation stack. Check the <param name="inputName"> tag specified for this action.

调试易

struts2 下载问题

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