传递动态参数注释？ [英] Passing dynamic parameters to an annotation?

问题描述

我用下面的注释：

  @Activati​​onConfigProperty（
    propertyName的=connectionParameters
    为PropertyValue =主机= 127.0.0.1，端口= 5445，主机= 127.0.0.1，端口= 6600），
公共类TestMDB实现消息驱动Bean，消息监听
 

我想拉这些IP地址和端口，并将它们存储在一个文件中 jmsendpoints.properties ...然后动态地加载它们。事情是这样的：

  @Activati​​onConfigProperty（
    propertyName的=connectionParameters
    的PropertyValue = jmsEndpointsProperties.getConnectionParameters（）），
公共类TestMDB实现消息驱动Bean，消息监听
 

有没有办法做到这一点？

解决方案

否注解处理器（您正在使用基于注解的框架）需要实现一个方法来处理占位符。

---

作为一个例子，一个类似的技术在<一个实施href=\"http://static.springsource.org/spring/docs/3.1.x/spring-framework-reference/html/\"><$c$c>Spring

  @Value（＃{systemProperties.dbName}）
 

下面<一个href=\"http://static.springsource.org/spring/docs/3.1.x/spring-framework-reference/html/ex$p$pssions.html\"><$c$c>Spring实现了一个方法的解析<​​/ em>的特定语法，在这种情况下，转换为类似的东西，以 System.getProperty（DBNAME）;

I am using the following annotation:

@ActivationConfigProperty(
    propertyName = "connectionParameters", 
    propertyValue = "host=127.0.0.1;port=5445,host=127.0.0.1;port=6600"),
public class TestMDB implements MessageDrivenBean, MessageListener

I would like to pull each of these IP addresses and ports and store them in a file jmsendpoints.properties... then load them dynamically. Something like this:

@ActivationConfigProperty(
    propertyName = "connectionParameters", 
    propertyValue = jmsEndpointsProperties.getConnectionParameters()),
public class TestMDB implements MessageDrivenBean, MessageListener

Is there a way to do that?

解决方案

No. The annotation processor (the annotation-based framework you're using) needs to implement an approach to handling placeholders.

---

As an example, a similar technique is implemented in Spring

@Value("#{systemProperties.dbName}")

Here Spring implements an approach to parsing that particular syntax, which in this case translates to something similar to System.getProperty("dbName");

这篇关于传递动态参数注释？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！