public String getUpdateToken() {
        return this.updateToken;
    }
<p>
A token used for optimistic locking. Network Firewall returns a token to your requests that access the rule
group. The token marks the state of the rule group resource at the time of the request.
</p>
<p>
To make changes to the rule group, you provide the token in your request. Network Firewall uses the token to
ensure that the rule group hasn't changed since you last retrieved it. If it has changed, the operation fails
with an <code>InvalidTokenException</code>. If this happens, retrieve the rule group again to get a current copy
of it with a current token. Reapply your changes as needed, then try the operation again using the new token.
</p>

@return A token used for optimistic locking. Network Firewall returns a token to your requests that access the
        rule group. The token marks the state of the rule group resource at the time of the request. </p>
        <p>
        To make changes to the rule group, you provide the token in your request. Network Firewall uses the token
        to ensure that the rule group hasn't changed since you last retrieved it. If it has changed, the
        operation fails with an <code>InvalidTokenException</code>. If this happens, retrieve the rule group
        again to get a current copy of it with a current token. Reapply your changes as needed, then try the
        operation again using the new token.
aws-java-sdk-networkfirewall/src/main/java/com/amazonaws/services/networkfirewall/model/DescribeRuleGroupResult.java