void addLogForwarders(ModelElement logForwardingElement, Admin admin, DeployState deployState) {
        if (logForwardingElement == null) return;
        boolean alsoForAdminCluster = logForwardingElement.booleanAttribute("include-admin");
        for (ModelElement e : logForwardingElement.children("splunk")) {
            LogForwarder.Config cfg = LogForwarder.cfg()
		    .withSplunkHome(e.stringAttribute("splunk-home"))
		    .withDeploymentServer(e.stringAttribute("deployment-server"))
		    .withClientName(e.stringAttribute("client-name"))
            .withPhoneHomeInterval(e.integerAttribute("phone-home-interval"))
            .withRole(parseLogforwarderRole(e.stringAttribute("role"), deployState));
            admin.setLogForwarderConfig(cfg, alsoForAdminCluster);
        }
    }
A base class for admin model builders, to support common functionality across versions.

@author Ulf Lilleengen
@author Vegard Havdal
config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomAdminBuilderBase.java