[Java] 當IE遇到不明副檔名會直接開啟該檔案的解決方法

遇到狀況：當IE遇到不明副檔名會直接開啟該檔案，改成用OutputStream的方式


response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", "attachment; filename="xxx.txt");

InputStream is = new FileInputStream("要下載檔案的Path");
OutputStream os = response.getOutputStream();

int n = 0;
byte[] ba = new byte[1024];

while((n = is.read(ba)) != -1){
os.write(ba, 0, n);
}

is.close();
out.flush();
out.close();

response.setStatus(response.SC_OK);
response.flushBuffer();