如何在没有传输编码的情况下发送HTTP响应：chunked？

Question

I have a Java Servlet that responds to the Twilio API. It appears that Twilio does not support the chunked transfer that my responses are using. How can I avoid using Transfer-Encoding: chunked ?

Here is my code:

// response is HttpServletResponse
// xml is a String with XML in it
response.getWriter().write(xml);
response.getWriter().flush();

I am using Jetty as the Servlet container.

Answer 1

I believe that Jetty will use chunked responses when it doesn't know the response content length and/or it is using persistent connections. To avoid chunking you either need to set the response content length or to avoid persistent connections by setting "Connection":"close" header on the response.

Answer 2

Try setting the Content-length before writing to the stream. Don't forget to calculate the amount of bytes according to the correct encoding, eg:

final byte[] content = xml.getBytes("UTF-8");
response.setContentLength(content.length);
response.setContentType("text/xml"); // or "text/xml; charset=UTF-8"
response.setCharacterEncoding("UTF-8");

final OutputStream out = response.getOutputStream();
out.write(content);

Answer 3

The container will decide itself to use Content-Length or Transfer-Encoding basing on the size of data to be written by using Writer or outputStream . If the size of the data is larger than the HttpServletResponse.getBufferSize() , then the response will be trunked. If not, Content-Length will be used.

In your case, just remove the 2nd flushing code will solve your problem.