Why doesn't Java's request.getAttributeNames() show Shibboleth attributes?

[Peter Schober]

* Philip Durbin <philip_durbin at harvard.edu> [2015-06-24 22:23]:
> Some day I might try to print out JkEnvVar to see if enumerate all
> the Shibboleth attributes I've received.

JkEnvVar /sets/ variables, and the mod_jk docs now state
"Note that the variables send via JkEnvVar will not be listed in
request.getAttributeNames()."
-peter