java - spring从非bean类访问代理bean

Question

我有一个 spring bean，它在其方法上使用 dropwizard-metrics 注释来测量一些指标(请参阅#parse 方法):

@Component
public class Consumer extends AbstractConsumer {

  @Autowired
  private EventsService eventsService;

  private ExecutorService executor;

  @PostConstruct
  void init() throws Exception {
    executor = Executors.newFixedThreadPool(1);

    ConsumerEventsHandler consumer = new ConsumerEventsHandler(Arrays.asList("topic1"), this);
    executor.submit(consumer);
  }

  @Timed(name = CONSUMER_BATCH_PARSING_TIME, absolute = true)
  public void parse(ConsumerRecord<String, String> record) {
    String val = record.value();
    eventsService.parseToDB(val);
  }
}

正如您所看到的，这个 bean 向执行程序服务提交了一个新任务，该任务不是一个 bean，但它需要对 Consumer bean 的引用来重用其逻辑(请参阅 consumer.解析(记录)；调用):

public class ConsumerEventsHandler implements Runnable {

private Consumer consumer;
private List<String> topics;
protected final KafkaConsumer<String, String> kafkaConsumer;

public ConsumerEventsHandler(List<String> topics, Consumer consumer) {
    this.topics = topics;
    this.consumer = consumer;
    this.kafkaConsumer = new KafkaConsumer<>();
}

@Override
public void run() {
    try {
        consumer.subscribe(topics);
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Long.MAX_VALUE);

            for (ConsumerRecord<String, String> record : records) {
                consumer.parse(record);
            }
        }
    } finally {
        consumer.close();
    }
}

}

这是指标配置(我使用“ryantenney/metrics-spring”lib):

@Configuration
@EnableMetrics(proxyTargetClass = true)
@ComponentScan(basePackages = "com.inq")
public class SsvpApiMetricsConfig extends MetricsConfigurerAdapter {
  @Resource
  private MetricRegistry registry;

  @PostConstruct()
  public void init() {
    configureReporters(registry);
  }

  @Override
  public void configureReporters(MetricRegistry metricRegistry) {

    registerReporter(JmxReporter.forRegistry(metricRegistry).
       inDomain("com.inq.metrics").build()).start();
  }
}

结果，我看到 Consumer bean 已被代理，但 ConsumerEventsHandler 包含对普通 bean 的引用，因为它是在 Consumer 的内创建的> 通过 'new ConsumerEventsHandler(..)' 的 @PostConstruct 方法 Consumer bean 尚未被代理，我假设 @PostConstruct 在代理事物之前被调用。

我看到的唯一解决方法是每次在 #run 方法内通过 ApplicationContext#getBean 获取Consumer bean ref，而不是将引用存储在 ConsumerEventsHandler 类变量中。还有其他解决办法吗？

Answer 1

只需在非 Spring 类上创建一个静态

public class ConsumerEventsHandler implements Runnable {

private static Consumer consumer;
private List<String> topics;
protected final KafkaConsumer<String, String> kafkaConsumer;

public ConsumerEventsHandler(List<String> topics) {
    this.topics = topics;
    this.kafkaConsumer = new KafkaConsumer<>();
}

public static setConsumer(Consumer consumer) {
    ConsumerEventsHandler.consumer = consumer;
}

然后在你的 Spring 一侧你可以有:

  @PostConstruct()
  public void init() {
    configureReporters(registry);
    ConsumerEventsHandler.setConsumer(consumer);
  }