SingletonServiceActivator.java

public class CustomSingletonElectionListener implements SingletonElectionListener {
    @Override
    public void elected(List<Node> candidateMembers, Node electedMember) {
        System.out.println("New singleton election: elected member " + electedMember + " from candidates " + candidateMembers);
    }
}




public class SingletonServiceActivator implements ServiceActivator {

    private static final String CONTAINER_NAME = "server";
    public static final ServiceName SERVICE_NAME = ServiceName.JBOSS.append("example", "service", "default");
    public static final String PREFERRED_NODE = "node-1";

    @Override
    public void activate(ServiceActivatorContext context) {
        SingletonServiceConfiguratorFactory factory = new ActiveServiceSupplier<SingletonServiceConfiguratorFactory>(context.getServiceRegistry(), ServiceName.parse(SingletonDefaultCacheRequirement.SINGLETON_SERVICE_CONFIGURATOR_FACTORY.resolve(CONTAINER_NAME))).get();
        ServiceTarget target = context.getServiceTarget();
        SingletonElectionListener listener = new CustomSingletonElectionListener();

        factory.createSingletonServiceConfigurator(SERVICE_NAME.append("singleton"))
                .electionPolicy(new PreferredSingletonElectionPolicy(new SimpleSingletonElectionPolicy(), new NamePreference(PREFERRED_NODE)))
                .electionListener(listener)
                .build(target)
                .install();
    }

}