... just like the Subversion polling does. Otherwise, the user will not notice
if the change trigger has an error.

Recently I was looking at once such installation where the URL change trigger
was failing with the following stack trace (because the URL in question is
protected), but the user had no way of noticing that, making it harder to
diagnose the problem.

pr 29, 2009 8:46:12 AM hudson.triggers.Trigger
WARNING: Cron thread throw an exception
java.lang.RuntimeException: java.io.IOException: Server returned HTTP response
code: 401 for URL: https://svn.dev.java.net/svn/glassfish-svn/trunk/v3
at com.redfin.hudson.UrlChangeTrigger.run(UrlChangeTrigger.java:136)
at hudson.triggers.Trigger.checkTriggers(Trigger.java:228)
at hudson.triggers.Trigger$Cron.doRun(Trigger.java:177)
at hudson.triggers.SafeTimerTask.run(SafeTimerTask.java:46)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Caused by: java.io.IOException: Server returned HTTP response code: 401 for URL:
https://svn.dev.java.net/svn/glassfish-svn/trunk/v3
at
sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1170)
at
sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234)
at java.net.URL.openStream(URL.java:1007)
at com.redfin.hudson.UrlChangeTrigger.run(UrlChangeTrigger.java:106)
... 5 more