private Roster getRoster(JID address) {
        String username;
        Roster roster = null;
        if (userManager.isRegisteredUser(address, false) || UserManager.isPotentialFutureLocalUser(address)) {
            username = address.getNode();
            try {
                roster = rosterManager.getRoster(username);
            }
            catch (UserNotFoundException e) {
                // Do nothing
            }
        }
        return roster;
    }
<p>Obtain the roster for the given address or null if the address doesn't have a roster.</p>

@param address The address to check
@return The roster or null if the address is not managed on the server
xmppserver/src/main/java/org/jivesoftware/openfire/handler/PresenceSubscribeHandler.java