Code review request: 7201053: Krb5LoginModule shows NPE when both useTicketCache and storeKey are set to true

[Weijun Wang]

Hi All

Please take a look at

   http://cr.openjdk.java.net/~weijun/7201053/webrev.00/

In fact, even without this code change, LoginContext would wrap the NPE 
inside a LoginException so no real harm will be made. However, it's 
always nice to check for null before reference a variable, and an NPE 
(no matter as a cause or in the message) is not user friendly.

Thanks
Max


-------- Original Message --------
7201053: Krb5LoginModule shows NPE when both useTicketCache and storeKey 
are set to true

=== *Description* 
============================================================
useTicketCache normally used in the intiator side, and storeKey on the 
acceptor side. When both are set to true, and a valid TGT is found 
inside the cache, no password or keytab will be required, and therefore 
no key to store.

This combination is useless and should have been set to illegal. 
However, some customers simply set a lot of arguments to true and this 
will actually work if password or key is used. We don't want to break 
their programs.

For this case, when there is no key but storeKey is true, a proper 
LoginException should be thrown. This is also consistent with the JDK 6 
behavior.