What is the proper way of setting headers in a URLConnection?

java header urlconnection
Geo picture Geo · Dec 1, 2008 · Viewed 42.8k times · Source

My code is like the following:

URLConnection cnx = address.openConnection();
cnx.setAllowUserInteraction(false);         
cnx.setDoOutput(true);
cnx.addRequestProperty("User-Agent", 
    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)");
InputStream is = cnx.getInputStream();

Is it ok if I set the headers before I get the InputStream? Will my header be sent, or will the server see the default URLConnection's user-agent ( if any ) ?

Answer

Ken Gentle picture Ken Gentle · Dec 1, 2008

The headers must be set prior to getting the InputStream to have any affect - an IllegalStateException will be thrown if the connection is already open.

As far as the User-Agent header specifically, it should be sent if it has been set.

See the URLConnection JavaDoc.

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