整数类型的值在 DeadLetterPublishingRecoverer 上出错

Question

我在这里试过这段代码：

@Bean
    public ConcurrentKafkaListenerContainerFactory<?, ?> kafkaListenerContainerFactory(
            ConcurrentKafkaListenerContainerFactoryConfigurer configure,
            ConsumerFactory<Object, Object> kafkaConsumerFactory,
            KafkaTemplate<Object, Object> template) {
        ConcurrentKafkaListenerContainerFactory<Object, Object> factory = new ConcurrentKafkaListenerContainerFactory<>();
        configure.configure(factory, kafkaConsumerFactory);
        factory.setErrorHandler(new SeekToCurrentErrorHandler(new DeadLetterPublishingRecoverer(template),3));
        return factory;
    }

这部分的整数

factory.setErrorHandler(new SeekToCurrentErrorHandler(new DeadLetterPublishingRecoverer(template),3));

不允许使用数字 3，因为它需要 BackOff 而不是 int 类型。

Answer 1

该构造函数已在 2.3.x 中弃用并在 2.5.x 中删除。

查看文档：https://docs.spring.io/spring-kafka/docs/current/reference/html/#seek-to-current

Previously, the configuration was "maxFailures" (which included the first delivery attempt). When using a FixedBackOff, its maxAttempts property represents the number of delivery retries (one less than the old maxFailures property). Also, maxFailures=-1 meant retry indefinitely with the old configuration, with a BackOff you would set the maxAttempts to Long.MAX_VALUE for a FixedBackOff and leave the maxElapsedTime to its default in an ExponentialBackOff.

现在相当于

factory.setErrorHandler(new SeekToCurrentErrorHandler(new DeadLetterPublishingRecoverer(template), new FixedBackOff(0L, 2));

（无延迟 3 次投递尝试）。