@Override
  public Membership<ID> create() throws MembershipConfigurationException {
    GMSMembership<ID> gmsMembership =
        new GMSMembership<>(membershipListener, messageListener, lifecycleListener);
    final Services<ID> services =
        new Services<>(gmsMembership.getGMSManager(), statistics, authenticator,
            membershipConfig, serializer, memberFactory, locatorClient, socketCreator);
    if (membershipLocator != null) {
      services.setLocators(membershipLocator.getGMSLocator(), membershipLocator);
    }
    services.init();
    return gmsMembership;
  }
MembershipBuilderImpl is the implementation of MembershipBuilder. It can construct
a GMSMembership.
geode-membership/src/main/java/org/apache/geode/distributed/internal/membership/gms/MembershipBuilderImpl.java