弹性4j-重试:1.7.1-不重试websocket连接

Question

我正在尝试连接到一个远程websocket端点(在spring引导应用程序中)，如果它抛出一个异常，我将使用弹性4j- retry v1.7.7和JDK 8重试连接。然而，弹性4j-重试尝试连接一次，如果失败，不要重试。我做错了什么，连接是在ApplicationReadyEvent上调用的。

    @Autowired
    private WsConnector connector;

    @Override
    public void onApplicationEvent(ApplicationReadyEvent event) {
        RetryConfig config = RetryConfig.custom()
                .maxAttempts(5)
                .waitDuration(Duration.ofSeconds(5))
                .build();

        RetryRegistry registry = RetryRegistry.of(config);
        Retry retry = registry.retry("retryableSupplier", config);

        CheckedFunction0<String> retryableSupplier = Retry.decorateCheckedSupplier(retry, connector::startConnection);
        try {
            System.out.println("retrying " + retryableSupplier.apply());
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }

        Retry.EventPublisher publisher = retry.getEventPublisher();
        publisher.onRetry(event1 -> System.out.println(event1.toString()));
        publisher.onSuccess(event2 -> System.out.println(event2.toString()));
    }

    @Service
    public class WsConnector {
        public String startConnection() throws Exception {
            WebSocketContainer container = ContainerProvider.getWebSocketContainer();
            WSClient client = new WSClient();
            container.connectToServer(client, new URI("ws://viewpoint:8080/ping"));
            return "Connected";
        }
    }

Answer 1

以下代码起作用了，

     @Override
    public void onApplicationEvent(ApplicationReadyEvent event) {
        RetryConfig config = RetryConfig.custom()
                .maxAttempts(5)
                .waitDuration(Duration.ofSeconds(5))
                .build();

        RetryRegistry registry = RetryRegistry.of(config);
        Retry retry = registry.retry("retryableSupplier", config);
        CheckedFunction0<String> checkedSupplier = Retry.decorateCheckedSupplier(retry, connector::startConnection);

        Retry.EventPublisher publisher = retry.getEventPublisher();
        publisher.onRetry(event1 -> System.out.println("Retrying: " + event1.toString()));
        publisher.onSuccess(event2 -> System.out.println("Retrying Success: " +event2.toString()));

        Try<String> result = Try.of(checkedSupplier).recover((throwable -> "I am recovered"));
        System.out.println("result: " + result);
    }

问题在于事件EventPublisher，但是在重试后我初始化了EventPublisher时，它是不可见的。因此，只要在启动重试之前对EventPublisher进行初始化，问题中的代码也将工作。我喜欢上面的代码更干净。