struts2文件下载类型的设置

<result name="success" type="stream">  <param name="contentType">image/jpeg</param>  <param name="inputName">imageStream</param>  <param name="contentDisposition">attachment;filename="document.pdf"</param><!--此处文件下载名为document.pdf-->  <param name="bufferSize">1024</param></result> 

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