title: Spring Qualifier and property placeholder
body: <p>Does anyone know if I should be able to use property placeholder as an expression in a Qualifier? I can't seem to get this working.</p>
  
  <p>I am using spring 3.0.4.</p>
  
  <pre><code>@Controller
  public class MyController {
     @Autowired
     @Qualifier("${service.class}")
     Service service;
  }
  
  @Service
  @Qualifier("ServiceA")
  ServiceA implements Service {
     public void print() {
         System.out.println("printing ServiceA.print()");
     } 
  }
  
  @Service
  @Qualifier("ServiceB")
  ServiceB implements Service {
     public void print() {
        System.out.println("printing ServiceB.print()");
     } 
  }
  </code></pre>
  
  <p>XML:</p>
  
  <pre><code>&lt;bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"&gt;
          &lt;property name="location" value="file:/etc/config.properties"/&gt;
  &lt;/bean&gt;
  </code></pre>
  
  <p>config.properties:</p>
  
  <pre><code>config.properties
  service.class=serviceB
  </code></pre>