Returns an immutable Set of X.509 attribute certificate
extensions that this PKIXAttrCertChecker supports or
null if no extensions are supported.
Each element of the set is a String representing the
Object Identifier (OID) of the X.509 extension that is supported.
All X.509 attribute certificate extensions that a
PKIXAttrCertChecker might possibly be able to process
should be included in the set.
an immutable Set of X.509 extension OIDs (inString format) supported by thisPKIXAttrCertChecker , or null if noextensions are supported |