Question

我希望能够从application.properties

设置@JMSlistener目标

我的代码看起来像这样

@Service
public class ListenerService {
    private Logger log = Logger.getLogger(ListenerService.class);

    @Autowired
    QueueProperties queueProperties;


    public ListenerService(QueueProperties queueProperties) {
        this.queueProperties = queueProperties;

    }

    @JmsListener(destination = queueProperties.getQueueName() )
    public void listenQueue(String requestJSON) throws JMSException {
        log.info("Received " + requestJSON);

    }
}

但在建造时我得到了

Error:(25, 60) java: element value must be a constant expression

Answer 1

您不能引用当前bean中的字段，但可以使用SpEL表达式在应用程序上下文中引用另一个bean ...

@SpringBootApplication
public class So49368515Application {

    public static void main(String[] args) {
        SpringApplication.run(So49368515Application.class, args);
    }

    @Bean
    public ApplicationRunner runner(JmsTemplate template, Foo foo) {
        return args -> template.convertAndSend(foo.getDestination(), "test");
    }

    @JmsListener(destination = "#{@foo.destination}")
    public void listen(Message in) {
        System.out.println(in);
    }

    @Bean
    public Foo foo() {
        return new Foo();
    }

    public class Foo {

        public String getDestination() {
            return "foo";
        }
    }

}

您还可以使用属性占位符${...}。

Answer 2

使用属性占位符要容易得多。

@JmsListener(destination = "${mq.queue}")
public void onMessage(Message data) {

}

从配置属性动态设置@JmsListener目标

2 个答案: