I'm following this example to create a JAVA class to manage Azure AD Users and Groups.
It uses the following library:
user = client.getAuthenticated().activeDirectoryUsers()
Based on my understanding, you want to update Azure AD Graph Users & Groups via Microsoft Azure SDK For Graph RBAC Management
com.microsoft.azure.management.graphrbac. I reviewed the current javadocs of Azure Graph RBAC Management, it seems to not support these attributes update operations you want now.
So by now, the effective way is directly using the Azure AD Graph APIs, please refer to the offical reference to know how to use it. And there is an offical code sample active-directory-java-graphapi-web that you can refer to.
Hope it helps.