java - itext pdf下载后无效

Question

当我下载已签名的 pdf 文档时，Adobe Reader 将其显示为无效。我可以在服务器上的本地项目文件夹中正常查看此文件，但是当我通过 servlet 下载此文件时，此下载过程中的某些内容会使 pdf 无效。这是我的 servlet 下载代码:

response.setContentType("application/pdf");
response.setHeader("Expires", "0");
response.setHeader("Cache-Control","must-revalidate, post-check=0, pre-check=0");
response.setHeader("Content-Disposition","inline;filename=CompensationReport" + compensation+".pdf");
response.setHeader("Accept-Ranges", "bytes");

FileInputStream fis = new FileInputStream(thePdf1);
BufferedInputStream bis = new BufferedInputStream(fis);
ServletOutputStream sos = response.getOutputStream();
byte[] buffer = new byte[2048];
while (true) {
    int bytesRead = bis.read(buffer, 0, buffer.length);
    if (bytesRead < 0) {
        break;
    }
    sos.write(buffer, 0, bytesRead);
    sos.flush();
}
sos.flush();
bis.close();  
return;

Answer 1

如上所述here尝试设置 Content-Length

response.setContentLength(filebytesize);