java有没有办法控制类在wildfly中部署的顺序

Question

此轮询服务用作库（jar文件）

@ApplicationScoped
public class PollingService {

@Inject
protected MessageConsumer consumer;

protected void init(@Observes @Initialized(ApplicationScoped.class) Object o) {
    final Set<String> subscribers = consumer.getSubscribers();
    //for each subscribers there's some task to execute.}}

而订阅服务器是由来自不同项目的其他应用程序范围的类添加的

@ApplicationScoped
public class MessageListener {
private static final Logger logger = LoggerFactory.getLogger(MessageListener.class);
private static final String TEST_QUEUE = "V3-shankar-test";

@Inject
private MessageConsumer consumer;

public void postConstruct(@Observes @Initialized(ApplicationScoped.class) Object o) {
    consumer.subscribe(TEST_QUEUE);
}

在MessageListener类添加订阅服务器之后，是否有任何方法初始化Pollingservice类

Answer 1

CDI中没有允许对同一范围内的bean进行初始化排序的机制（@ApplicationScoped在上面的示例中）

CDI还提供了其他可供使用的功能：

1. ^{}
2. 触发特定于应用程序的事件

---

带有Instance的代码示例：

@ApplicationScoped
public class PollingService {

    @Inject
    @Any
    protected Instance<MessageListener> listeners;

    protected void init(@Observes @Initialized(ApplicationScoped.class) Object o) {
        for (MessageListener listener : listeners) {
            //for each subscribers there's some task to execute.
        }
    }

}

这里可以通过检测实际listener类上的注释来引入优先级处理，因为代码显式地处理列表

---

具有应用程序特定事件的代码示例：

public class PollingServiceInit {
    private final PollingService service;
    ...

    public void subscribe(MessageConsumer consumer) {
        service.subscribe(consumer);
    }
}

@ApplicationScoped
public class PollingService {

    @Inject
    private Event<PollingServiceInit> event;

    protected void init(@Observes @Initialized(ApplicationScoped.class) Object o) {
        event.fire(new PollingServiceInit(this));
    }

    void subscribe(MessageListener listener) {
        //for each subscribers there's some task to execute.
    }

}

@ApplicationScoped
public class MessageListener {
    void onPollingServiceInit(@Observes final PollingServiceInit event) {
        event.subscribe(this);
    }
}

Answer 2

您可以在每个示例的o参数上放置^{}。通常，它的int类型的元素值是从^{}类的常量中提取或扩充的。观察员方法通知上的specification goes into some detail