java MDB 注释的可配置值
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Configurable values to MDB annotations
提问by Sietse
I'm trying to use this methodfor receiving mail in our EJB3 app. In short, that means creating an MDB with the following annotations:
我正在尝试使用此方法在我们的 EJB3 应用程序中接收邮件。简而言之，这意味着创建一个带有以下注释的 MDB：
@MessageDriven(activationConfig = { @ActivationConfigProperty(propertyName = "mailServer", propertyValue = "imap.company.com"),
@ActivationConfigProperty(propertyName = "mailFolder", propertyValue = "INBOX"),
@ActivationConfigProperty(propertyName = "storeProtocol", propertyValue = "imap"),
@ActivationConfigProperty(propertyName = "debug", propertyValue = "false"),
@ActivationConfigProperty(propertyName = "userName", propertyValue = "username"),
@ActivationConfigProperty(propertyName = "password", propertyValue = "pass") })
@ResourceAdapter("mail-ra.rar")
@Name("mailMessageBean")
public class MailMessageBean implements MailListener {
public void onMessage(final Message msg) {
...snip...
}
}
I have this working, but the situation is less than ideal: The hostname, username and password are hardcoded. Short of using ant and build.properties to replace those values before compilation, I don't know how to externalize them.
我有这个工作，但情况不太理想：主机名、用户名和密码是硬编码的。在编译之前没有使用 ant 和 build.properties 来替换这些值，我不知道如何将它们具体化。
It would be ideal to use an MBean, but I have no idea how to get the values from the MBean to the MDB configuration.
最好使用 MBean，但我不知道如何将值从 MBean 获取到 MDB 配置。
How should I do this?
我该怎么做？
回答by Brett Hannah
You can externalise the annotations into the ejb-jar.xml that you deploy in the META-INF of your jar file as follows:
您可以将注释外部化到您在 jar 文件的 META-INF 中部署的 ejb-jar.xml 中，如下所示：
<?xml version="1.0" encoding="UTF-8"?>
<ejb-jar version="3.0">
<enterprise-beans>
<message-driven>
<ejb-name>YourMDB</ejb-name>
<ejb-class>MailMessageBean</ejb-class>
<activation-config>
<activation-config-property>
<activation-config-property-name>username</activation-config-property-name>
<activation-config-property-value>${mdb.user.name}</activation-config-property-value>
</activation-config-property>
...
...
</activation-config>
</message-driven>
</enterprise-beans>
Then you can set the mdb.user.name value as a system property as part of the command line to your application server using -Dmdb.user.name=theUserName and it will magically get picked up by the mdb.
然后，您可以使用 -Dmdb.user.name=theUserName 将 mdb.user.name 值设置为系统属性，作为应用程序服务器命令行的一部分，它会神奇地被 mdb 接收。
Hope that helps.
希望有帮助。
回答by Joseph Valerio
As of JBoss AS 5.1 at least, you can use AOP to configure the @ActivationConfigProperties. I discovered this by looking at the examples that jboss provides here. This is useful if you do not want your username and passwords available to the entire container in a systems property, or if you are like me and never, I repeat NEVER, want to deploy an artifact with a username/password in it. Any how, here is the jist...
至少从 JBoss AS 5.1 开始，您可以使用 AOP 来配置 @ActivationConfigProperties。我通过查看 jboss在此处提供的示例发现了这一点。如果您不希望系统属性中的整个容器都可以使用您的用户名和密码，或者如果您像我一样并且从不，我再说一遍，从不希望部署包含用户名/密码的工件，这将非常有用。不管怎样，这里是 jist...
Annotate the mdb like this...
像这样注释mdb...
...
@MessageDriven
@AspectDomain("TestMDBean")
public class TestMDBean implements MessageListener {
...
Then add a ${whatever}-aop.xml to the deploy dir with internals like below. I left the original comments in there in case Jaikiran does make the changes mentioned...
然后将 ${whatever}-aop.xml 添加到部署目录，内部结构如下所示。我在那里留下了原始评论，以防 Jaikiran 确实进行了提到的更改......
Note: the annotation must be on one line only.
注意：注释只能在一行上。
<?xml version="1.0" encoding="UTF-8"?>
<aop xmlns="urn:jboss:aop-beans:1.0">
<!-- TODO: Jaikiran - These interceptor declarations need not be here since they
are already declared through the ejb3-interceptors-aop.xml. Duplicating them leads to
deployment errors. However, if this custom-ejb3-interceptors-aop.xml needs to be
independent, then we must find a better way of declaring these. Right now, commenting these
out, can be looked at later. -->
<!--
<interceptor class="org.jboss.ejb3.AllowedOperationsInterceptor" scope="PER_VM"/>
<interceptor class="org.jboss.ejb3.entity.TransactionScopedEntityManagerInterceptor" scope="PER_VM"/>
<interceptor factory="org.jboss.ejb3.security.RunAsSecurityInterceptorFactory" scope="PER_CLASS"/>
<interceptor class="org.jboss.ejb3.stateless.StatelessInstanceInterceptor" scope="PER_VM"/>
<interceptor factory="org.jboss.ejb3.interceptor.EJB3InterceptorsFactory" scope="PER_CLASS_JOINPOINT"/>
<interceptor factory="org.jboss.aspects.tx.TxInterceptorFactory" scope="PER_CLASS_JOINPOINT"/>
-->
<domain name="TestMDBean" extends="Message Driven Bean" inheritBindings="true">
<annotation expr="!class(@org.jboss.ejb3.annotation.DefaultActivationSpecs)">
@org.jboss.ejb3.annotation.DefaultActivationSpecs (value={@javax.ejb.ActivationConfigProperty(propertyName="destinationType", propertyValue="javax.jms.Queue"), @javax.ejb.ActivationConfigProperty(propertyName="destination", propertyValue="queue/MyQueue"), @javax.ejb.ActivationConfigProperty(propertyName="user", propertyValue="testusr"), @javax.ejb.ActivationConfigProperty(propertyName="password", propertyValue="testpwd")})
</annotation>
</domain>
</aop>
