NPE when registry lookup does not resolve

[pdowler]

java.lang.NullPointerException: Cannot invoke "java.net.URL.toExternalForm()" because "usersURL" is null
        at ca.nrc.cadc.ac.client.UserClient.augmentSubject(UserClient.java:156)
        at ca.nrc.cadc.ac.ACIdentityManager$1.run(ACIdentityManager.java:174)

This happens if the standardID in cadc-registry.properties does not resolve in a query to a configured reg; found when testing multiple registries with different content.

[pdowler]

This is when using the latest cadc-registry (not published, but likely 1.9.0) where it can now return a null URL rather than throw an exception, so I will look back at the old behaviour of RegistryClient and see whether null or ResourceNotCoundException is actually better. TBD