Spring Qualifier and property placeholder

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This works. You can leave off the service names if you just use the default spring bean name. serviceA vs ServiceA, etc.

@Controller
class MyController {
@Autowired(required=false)
@Qualifier("Service")
Service service;

public static void main(String[] args) {
   ApplicationContext context = new ClassPathXmlApplicationContext("app-ctx.xml", MyController.class);
   for(String s:context.getBeanDefinitionNames()){
       System.out.println(s);
       for(String t:context.getAliases(s)){
           System.out.println("\t" + t);
       }
   }
   context.getBean(MyController.class).service.print();
  }
}

public interface Service {
    void print();
}

@Service(value="ServiceA")
public class ServiceA implements example.Service {
    public void print() {
        System.out.println("printing ServiceA.print()");
    } 
}

@Service(value="ServiceB")
public class ServiceB implements example.Service {
    public void print() {
        System.out.println("printing ServiceB.print()");
    } 
}

XML: 

<beans>
    <alias name="${service.class}" alias="Service"/>
    <context:property-placeholder location="example/app.properties"/>
    <context:component-scan base-package="example"/>
<beans>

Props:

service.class=ServiceB

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