Add the following words somewhere inside the SASL mechanisms part of the Oracle Providers doc [1]:
 
  com.sun.security.jgss.inquiretype.<type_name> for GSSAPI mechanism:
 
  The name of a negotiated property that is the value returned by
  ExtendedGSSContext.inquireSecContext(InquireType type), where
  "type_name" is the string form of the InquireType enum parameter,
  in lower case.
 
[1] http://docs.oracle.com/javase/8/docs/technotes/guides/security/SunProviders.html#SunSASLProvider