URLConnections for HTTP URLs allows getOutputStream to return a stream, ignoring
doOutput. That is, if doOutput is false, you will still get a stream back from getOutputStream

The description field as copied from bug report 1262772 follows:

The URLConnection implementaiton for HTTP URLs doesn't check the doOutput
flag before returning an output stream from getOutputStream. This lets one get
a connection on which output should not be done.

The description field as copied from bug report 1262574 follows:

I can get an output stream from an HTTP URL connection even if doOutput is false

This is the root of our belief that Netscape "doesn't allow POST". It does, but they
reasonably require that doOutput be true before the will return an output stream
to a URL. We ignore the flag. We shouldn't.