kafka consumer start error

[amwyyyy]

Please answer these questions before submitting your issue.

• Why do you submit this issue?
• Question or discussion
• [ x ] Bug
• Requirement
• Feature or performance improvement

---

Bug

version:
SkyWalking7.0.0
spring-kafka:2.2.8.RELEASE
kafka-clients:2.0.1

When kafka consumer uses topicPattern, the agent will report an error.

@KafkaListener(topicPattern = KAFKA_TOPIC_NAME)
public void onDemoMessage(ConsumerRecord<String, String> record) {
// ...
}

skywalking-api.log

ERROR 2020-06-05 17:57:30:137 restartedMain InstMethodsInter : class[class org.apache.kafka.clients.consumer.KafkaConsumer] before method[subscribe] intercept failure 
java.lang.ClassCastException: java.util.regex.Pattern cannot be cast to java.util.Collection
	at org.apache.skywalking.apm.plugin.kafka.SubscribeMethodInterceptor.beforeMethod(SubscribeMethodInterceptor.java:33)
	at org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstMethodsInter.intercept(InstMethodsInter.java:76)
	at org.apache.kafka.clients.consumer.KafkaConsumer.subscribe(KafkaConsumer.java)
	at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.subscribeOrAssignTopics(KafkaMessageListenerContainer.java:584)

[wu-sheng]

This seems a plugin incompatible case. Most plugins are contributed by the users, so, please try to learn the plugin development( we provided doc), and add supports to this case. We are welcome your contribution.