@SuppressWarnings("AccessStaticViaInstance")
    public static UserProvider getUserProvider() {
        return UserManagerContainer.instance.provider;
    }
Returns the currently-installed UserProvider. <b>Warning:</b> in virtually all
cases the user provider should not be used directly. Instead, the appropriate
methods in UserManager should be called. Direct access to the user provider is
only provided for special-case logic.

@return the current UserProvider.
xmppserver/src/main/java/org/jivesoftware/openfire/user/UserManager.java