我正在尝试在Struts Action类中下载PDF文件.

问题是使用

response.setHeader("Content-Disposition", "attachment;filename=file.pdf");

我想打开“保存/打开”框,但现在PDF内容在浏览器中写入：

恩.

%PDF-1.4 28 0 obj << /Type /XObject /Subtype /Image /Filter /DCTDecode /Length 7746 /Width 200 /Height 123 /BitsPerComponent 8 /ColorSpace /DeviceRGB >>...(cut)

我在Chrome,Firefox和IE下尝试了这个代码(下面),到处都是这样.我也使用不同的PDF文件.

我的代码片段：

try {

URL fileUrl = new URL("file:///" + filePath);

URLConnection connection = fileUrl.openConnection();

inputStream = connection.getInputStream();

int fileLength = connection.getContentLength();

byte[] outputStreamBytes = new byte[100000];

response.setContentType("application/pdf");

response.setHeader("Content-Disposition", "attachment;filename=file.pdf");

response.setContentLength(fileLength);

outputStream = response.getOutputStream();

int iR;

while ((iR = inputStream.read(outputStreamBytes)) > 0) {

outputStream.write(outputStreamBytes, 0, iR);

}

return null;

} catch (MalformedURLException e) {

logger.debug("service", "An error occured while creating URL object for url: "

+ filePath);

response.sendError(HttpServletResponse.SC_NOT_FOUND);

return null;

} catch (IOException e) {

logger.debug("service", "An error occured while opening connection for url: "

+ filePath);

response.sendError(HttpServletResponse.SC_NOT_FOUND);

return null;

} finally {

if (outputStream != null) {

outputStream.close();

}

if (inputStream != null) {

inputStream.close();

}

inputStream.close();

}

return null;

还缺少什么？

编辑

当我在Struts类中使用此代码时,它不起作用,但是当我在Servlet中使用此代码时,它正在工作.

最奇怪的是,当我在动作类中只将“response.sendRedirect()”写入Servlet(并且所有逻辑都在Servlet中)时,它也不起作用.

当我分析响应头时,这三个例子中的所有内容都是相同的.