Java, HttpURLConnection and setting the content length

Question

I'm setting the length of the content in my HttpURLConnection, for a PUT.

urlConnection.setRequestProperty("Content-Length", "" + responseJSONArray.toString(2).getBytes("UTF8").length);

The actual number of bytes is 74. However, when I query the content length of urlConnection I'm returned -1. Why is that? And why are lengths not equal (given that I set this)?

I must set the content-length because I'm receiving a 411 response from the server.

(Also, in the Sun examples I've seen the second argument of setRequestProperty is of type int and not String, which seems odd.)

I answered this question and I realise now that it's got an android tag. I have no idea how Google implemented `HttpURLConnection`. — Buhake Sindi, Aug 15 '11 at 08:41
@The Elite Gentleman they would have had to agree with the existing Javadoc specification, and your misunderstandings didn't have anything to do with possible variations among implementations. — user207421, Aug 22 '11 at 10:22

score 26 · Accepted Answer · answered Aug 15 '11 at 07:05

26

You shouldn't set this header yourself. Use setFixedLengthStreamingMode() or setChunkedTransferMode().

answered Aug 15 '11 at 07:05

user207421

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Thanks. I still don't understand something: I'm now doing `urlConnection.setFixedLengthStreamingMode(responseJSONArray.toString(2).getBytes("UTF8").length);`. The body-length is `74` bytes, however when I call `Log.v("app", "" + urlConnection.getContentLength());` I see `-1`. Why is that? – Ken Aug 15 '11 at 07:14
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@SK9 that's the length of the *response.* – user207421 Aug 15 '11 at 08:20
Thanks. That seems needlessly ambiguous to me! – Ken Aug 15 '11 at 08:27
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@SK9 nothing ambiguous about it. There is no reference in the Javadoc to the content length of the request. It is all about the response. – user207421 Aug 16 '11 at 00:16
@SK9 of course, but you asked about `getContentLength(),` which is what I answered about. – user207421 Aug 18 '11 at 11:33
I have set setFixedLengthStreamingMode(), but i getContentLength() still return -1 at server client. Is there someone solve this problem? – boiledwater Apr 12 '12 at 10:07
@boiledwater Did you set it before you started to write the output? – user207421 Apr 13 '12 at 04:24
@boiledwater Why? It says exactly what I have told you here. – user207421 Apr 19 '12 at 03:31

score 3 · Answer 2 · answered Aug 15 '11 at 07:13

3

Also do not forget to add a setDoOutput to tell your connection you are going to send data.

answered Aug 15 '11 at 07:13

Nicolas Modrzyk

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Thanks. I already am (with `urlConnection.setDoOutput(true);`). – Ken Aug 15 '11 at 07:15
It should rightfully be -1, since you are sending data not getting some from the server. getContentLenght(): "Returns the content length in bytes specified by the response header field content-length or -1 if this field is not set." From [Android Javadoc for HttpURLConnection](http://developer.android.com/reference/java/net/HttpURLConnection.html) – Nicolas Modrzyk Aug 15 '11 at 07:39
1

Hmm - I thought the content-length field specified the byte-length of the HTTP request I was preparing. – Ken Aug 15 '11 at 07:44
1

What should be -1? The question is about the request content-length. Your quotation is about the response content-length. Your remark doesn't make sense. – user207421 Oct 21 '16 at 23:40

score -2 · Answer 3 · answered Aug 27 '18 at 16:06

I get same error with "Content-Length" -

        URL url = new URL(targetURL);
        connection = (HttpURLConnection) url.openConnection();
        connection.setRequestMethod("POST");
        connection.setRequestProperty("Content-Type", "text/plain");
        connection.setRequestProperty("Authorization", authKey);
        connection.setRequestProperty("Content-Length", Integer.toString(requestJSON.getBytes().length));

And I finally deduced that it happens because one of the Json object fields contains diacritical characters.

        someCategory = "Ţepuşă";
        try {
        JSONObject postData = new JSONObject();
        postData.put("category", someCategory);
        .....

That's what the error looks like:

08-27 18:57:07.842 24263-24263/ro.nexuserp.documentecontabile E/Eror: content-length promised 491001 bytes, but received 491000

The error is that you shouldn't set it at all. Java will set it for you. This was stated, several times, eight years before you posted. — user207421, Sep 23 '19 at 11:36

Java, HttpURLConnection and setting the content length

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