How to Fetch UserSMIMECertificate, UserCertificate or PRUserX509Certificate in Microsoft Graph API.

In MS EWS there are xmlelements like contacts:MSExchangeCertificate,  contacts:UserSMIMECertificate. How can we fetch those using graph API. I don't see any properties for them in User POJO or Contact in Graph SDK for Java. Please Guide me with this.

Thanks in Advance.