How to set content-length in android?

问题

I want to get content size by request.getContentLength() in server client JSP page. But request.getContentLength() always return -1, i do not why?

Android snippet code:

URL uri = new URL(actionUrl);
HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
//conn.setChunkedStreamingMode(100);
conn.setConnectTimeout(setTimeOut>0?setTimeOut:timeoutConnection);
conn.setReadTimeout(setTimeOut>0?setTimeOut:timeoutConnection);  
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "keep-alive");

//conn.setRequestProperty("content-length", "10");
//conn.addRequestProperty("content-length", "20");
conn.setFixedLengthStreamingMode(30);

conn.setRequestProperty("Charsert", ENCODING);
conn.setRequestProperty("Content-Type", "multipart/form-data"
                + ";boundary=" + java.util.UUID.randomUUID().toString());
conn.connect();

回答1:

You are using conn.setChunkedStreamingMode(100) that will effectively enable the chunked transfer encoding in chunks of 100 bytes when the content-lenght is unknown in advance.

Use conn.setFixedLengthStreamingMode(int len) if you know in advance the length of the content you are going to send in the body of the request.

来源：https://stackoverflow.com/questions/10121677/how-to-set-content-length-in-android