在部署时更改主题读取MDB的激活配置

问题描述

我觉得这应该很容易。只是RTM然后去。但我找不到我需要的信息。

I feel this should be easy. Just RTM and go. But I can't find the info I need.

问：我可以更改 @ActivationConfigProperty的值在部署时无需编写任何XML？

Q: Can I change the value of an @ActivationConfigProperty at deploy time without having to write any XML?

我有一个使用 @MessageDriven 注释的MDB。其中有一些 @ActivationConfigProperty 注释配置它。

I have an MDB which is using the @MessageDriven annotation. Within this are a number of @ActivationConfigProperty annotations configuring it.

@MessageDriven(mappedName = "jms/TestJeremyTopic ", activationConfig = {
        @ActivationConfigProperty(propertyName = "acknowledgeMode", propertyValue = "Auto-acknowledge"),
        @ActivationConfigProperty(propertyName = "destinationType", propertyValue = "javax.jms.Topic"),
        @ActivationConfigProperty(propertyName = "subscriptionDurability", propertyValue = "Durable"),
        @ActivationConfigProperty(propertyName = "clientId", propertyValue = "TopicReaderBeanClientId"),
        @ActivationConfigProperty(propertyName = "subscriptionName", propertyValue = "TopicReaderBeanSubscriptionName")
})
public class TopicReaderBean implements MessageListener { // ...

我需要多次部署此MDB，每次都会引用不同的主题。

I need to deploy this MDB multiple times, referring to a different topic each time.

在部署时（WebSphere 7 N. D）我能够为每个EAR配置不同的 TopicListenerPort （WebSphere的映射到不同主题的方式）。但是，当我尝试启动第二个实例时，它失败并显示错误：

At deploy time (WebSphere 7 ND) I am able to configure a distinct TopicListenerPort (WebSphere's way of mapping to different topics) for each EAR. However when I try to start a second instance it fails with the error:

当我查看MQ Explorer时，我可以看到订阅名称是 JMS：GGWKNNG5：gmm_poc_06：TopicReaderBeanSubscriptionName 这是一个JMS，QueueManager名称，主题连接工厂ID和ActivationConfigPropertysubscriptionName的组合。第二个连接因此订阅名称发生冲突而失败。我需要区分不同MDB实例使用的订阅名称。

When I look to MQ Explorer I can see the subscription name is JMS:GGWKNNG5:gmm_poc_06:TopicReaderBeanSubscriptionName This is a composition of "JMS", QueueManager name, Topic Connection Factory ID, and ActivationConfigProperty "subscriptionName". The second connection fails because of a clash on this subscription name. I need to distinguish the subscription names used by distinct MDB instances.

虽然我可以为每个bean创建一个新的主题连接工厂，但这将是很多工作并且不会没有多大意义。

Whilst I could create a new Topic Connection Factory for each bean, it would be a lot of work and doesn't make much sense.

有意义的是每个bean有一个不同的订阅名称。但是这个属性被添加到注释中，我无法在WebSphere中看到允许我覆盖它的任何地方。

What does make sense is to have a different subscription name per bean. However this property is baked into the annotation and I can't see anywhere in WebSphere that would allow me to override it.

因此，我可以覆盖此属性而不必编写XML部署描述符？如果我做需要编写一些XML，我该如何覆盖其中的属性？

So, can I override this property without having to write an XML deployment descriptor? And if I do need to write some XML, how do I override the property therein?

推荐答案

代替任何部署时解决方案，我编写了一个 ejb-jar.xml 配置，我可以在构建时修改它。它如下所示：

In lieu of any deploy-time solution I've written an ejb-jar.xml config that I can modify at build time. It reads thus:

<?xml version="1.0"?>
 <ejb-jar xmlns="http://java.sun.com/xml/ns/javaee"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_1.xsd"
      version="3.1">
    <enterprise-beans>

        <message-driven id="MySpecialMDB">
            <display-name>MySpecialMDB</display-name>
            <ejb-name>TopicReaderBean</ejb-name>
            <ejb-class>my.TopicReaderBean</ejb-class>
            <transaction-type>Container</transaction-type>
            <message-destination-type>javax.jms.Topic</message-destination-type>
            <activation-config>
                <activation-config-property>
                    <activation-config-property-name>destinationType</activation-config-property-name>
                    <activation-config-property-value>javax.jms.Topic</activation-config-property-value>
                </activation-config-property>
                <activation-config-property>
                    <activation-config-property-name>subscriptionDurability</activation-config-property-name>
                    <activation-config-property-value>Durable</activation-config-property-value>
                </activation-config-property>
                <activation-config-property>
                    <activation-config-property-name>subscriptionName</activation-config-property-name>
                    <activation-config-property-value>${subscriptionName}</activation-config-property-value>
                </activation-config-property>
            </activation-config>
        </message-driven>

    </enterprise-beans>
</ejb-jar>

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