一个Spring的Kafka消费者听众可以收听多个主题吗？

Question

有人知道一个听众是否可以听下面这样的多个话题吗？我知道“主题1”很管用，如果我想添加其他主题呢？你能给我举个例子吗？谢谢你的帮助！

@KafkaListener(topics = "topic1,topic2")
public void listen(ConsumerRecord<?, ?> record, Acknowledgment ack) {
    System.out.println(record);
} 

或者

ContainerProperties containerProps = new ContainerProperties(new TopicPartitionInitialOffset("topic1, topic2", 0));

Answer 1

是的，只需遵循@KafkaListenerJavaDocs：

/**
 * The topics for this listener.
 * The entries can be 'topic name', 'property-placeholder keys' or 'expressions'.
 * Expression must be resolved to the topic name.
 * Mutually exclusive with {@link #topicPattern()} and {@link #topicPartitions()}.
 * @return the topic names or expressions (SpEL) to listen to.
 */
String[] topics() default {};

/**
 * The topic pattern for this listener.
 * The entries can be 'topic name', 'property-placeholder keys' or 'expressions'.
 * Expression must be resolved to the topic pattern.
 * Mutually exclusive with {@link #topics()} and {@link #topicPartitions()}.
 * @return the topic pattern or expression (SpEL).
 */
String topicPattern() default "";

/**
 * The topicPartitions for this listener.
 * Mutually exclusive with {@link #topicPattern()} and {@link #topics()}.
 * @return the topic names or expressions (SpEL) to listen to.
 */
TopicPartition[] topicPartitions() default {};

因此，您的用例应该是：

@KafkaListener(topics = {"topic1" , "topic2"})