one:

Struts.xml

<result name="success" type="stream"><!-- ;charset=UTF-8  ;charset=ISO-8859-1-->

    <param name="contentType">application/octet-stream</param>       <param name="contentDisposition">attachment;filename=${fileName}</param>     <param name="inputName">fileinputstream</param>     <param name="bufferSize">4096</param>    </result>

two:

 private FileInputStream fileinputstream;

 private String fileName;

/**

  * 下载文件   */  public InputStream getFileinputstream(){ //  ServletActionContext.getResponse().setContentType("application/octet-stream;charset=UTF-8");   try {

   String s=(String) Constants.SIDECODE_LIST[Constants.SIDECODE_IN_STATE][2];    String url=this.getFileUrl().replace("", s);  //這裡你可以自己配置路徑

   fileinputstream = new FileInputStream(new File(url));   } catch (Exception e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return fileinputstream;  }

 public void setFileinputstream(FileInputStream fileinputstream) {

  this.fileinputstream = fileinputstream;  }

/**

  * 防止IE，火狐乱码   *   */

 public String getFileName() {

  if(fileName!=null){    try {     HttpServletRequest request = ServletActionContext.getRequest();             String Agent = request.getHeader("User-Agent");             if (null != Agent) {                 Agent = Agent.toLowerCase();                 if (Agent.indexOf("firefox") != -1) {                  fileName = new String(fileName.getBytes(),"ISO-8859-1");   //               fileName = StringUtils.replace(fileName, " ", "%20");               } else if (Agent.indexOf("msie") != -1) {                  fileName = java.net.URLEncoder.encode(fileName,"UTF-8");                 fileName = StringUtils.replace(fileName, "+", "%20");               } else {                  fileName = java.net.URLEncoder.encode(fileName,"UTF-8");                  fileName = StringUtils.replace(fileName, "+", "%20");               }             } 

   } catch (Exception e) {

    // TODO Auto-generated catch block     e.printStackTrace();    }     return fileName;   }   return "";  }  public void setFileName(String fileName) {   this.fileName = fileName;  }