saving to file and guunzip results in invalid format The actual java code sending the data looks like this

urlos = connection.getOutputStream();
if(compress)
{bufos = new BufferedOutputStream(new GZIPOutputStream(urlos));
            } else
            {
                bufos = new BufferedOutputStream(urlos);
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so I assume that the data is GZIP compressed before being sent by java app and the switch to not use compress was not coded so it is always compressed