public void setUpdateToken(String updateToken) {
        this.updateToken = updateToken;
    }
<p>
A token used for optimistic locking. Network Firewall returns a token to your requests that access the firewall
policy. The token marks the state of the policy resource at the time of the request.
</p>
<p>
To make changes to the policy, you provide the token in your request. Network Firewall uses the token to ensure
that the policy 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 firewall policy again to get a current copy of
it with current token. Reapply your changes as needed, then try the operation again using the new token.
</p>

@param updateToken
       A token used for optimistic locking. Network Firewall returns a token to your requests that access the
       firewall policy. The token marks the state of the policy resource at the time of the request. </p>
       <p>
       To make changes to the policy, you provide the token in your request. Network Firewall uses the token to
       ensure that the policy 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 firewall policy again to get a
       current copy of it with 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/CreateFirewallPolicyResult.java