Spring限定符和属性占位符

这可行。如果仅使用默认的spring bean名称，则可以省略服务名称。serviceA与ServiceA等

@Controllerclass 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