This code doesn't work:
URL url = new URL( xmlPath );
InputSource input = new InputSource( url.openStream() );
all the time, resulting in an UnknownHostException, even when the host exists, has been hit successfully using the same code if from a different development host (machine), and also from a browser.
I'm probably out of line asking this question again, a repeat of Android java.net.UnknownHostException: Host is unresolved (strategy question). The forum software would not allow me to comment on the unsatisfactory answer to that question (in order to solicit more attention to the solution I ultimately found). Perhaps I'm not popular enough yet to be given that privilege. In the meantime, I'm essentially re-posting the question and a different answer.
Basically, I accept that maybe the Android device has a hard time with DNS under certain circumstances, but I've tried, for example the anddev.org example of how to use the SAX parser, and it worked on one machine I have and not on another.
Edit: As noted, I know a working answer and will post it.
I am a) asking a question (that's already been asked and unsuccessfully answered) and b) answering it for the benefit of those for whom my answer will be useful.