java - Wildfly 10.1.0 单例不起作用

Question

我在一个域中配置了两个 Wildfly 服务器，并且我需要创建一个使用 HA 运行的单例。我需要它只在一台服务器上运行，如果该服务器发生故障，它应该在从属服务器中启动。我使用默认配置，并且只在 WAR 中创建了“/META-INF/singleton-deployment.xml”。当我部署 WAR 时，它会在两台服务器中启动!不仅在一处。缺什么？我需要在domain.xml 中编辑某些内容吗？

我的单例仅将文本写入日志文件和控制台，仅用于测试:

import java.net.InetAddress;
import java.net.UnknownHostException;
import javax.ejb.ConcurrencyManagement;
import javax.ejb.ConcurrencyManagementType;
import javax.ejb.Schedule;
import javax.ejb.Singleton;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

@ConcurrencyManagement(ConcurrencyManagementType.CONTAINER)
@Singleton
public class TesteAPP {

    final Logger logger = LogManager.getLogger(TesteAPP.class);

    @Schedule(second = "*/1", minute = "*", hour = "*", persistent = false)
public void executaTarefa() {
    try {
        logger.log(Level.INFO, "Tarefa executada com sucesso! Nome da         máquina: {} Endereço da máquina: {}",
                InetAddress.getLocalHost().getHostName(),
                InetAddress.getLocalHost().getHostAddress());
        System.out.println(String.format("Tarefa executada com sucesso! Nome da máquina: %s Endereço da máquina: %s",
                InetAddress.getLocalHost().getHostName(),
                InetAddress.getLocalHost().getHostAddress()));
    } catch (UnknownHostException e) {
        logger.log(Level.ALL, "Tarefa executada com sucesso!");
        System.out.println(String.format("Tarefa executada com sucesso!"));
    }
}


}

Answer 1

已在 https://stackoverflow.com/a/27956003/653069 中得到答复

根据 EJB 3.1 规范，@Singleton 仅适用于每个 JVM，而不适用于每个集群。

In cases where the container is distributed over many virtual machines, each application will have one bean instance of the Singleton for each JVM.

尽管如此，您可以使用 JBoss 特定的方式。看看cluster-ha-singleton quickstart - EAP 7.0 之一，也应该适用于 WildFly 10.x。