我正在尝试使用骆驼向kafka发送消息 . 我从camel git repo中获取了camel示例代码 . 我运行MessagePublisherClient.java并得到以下异常 . 我在属性文件中配置了我的Kafka服务器名称，端口和主题详细信息 .
为什么我得到此异常以及如何修复此异常 .
如果我尝试使用camel 2.14.1版本并根据2.14.1进行代码更改 . 我能够推送消息 . 但为什么最新版本会出错 .
骆驼回购：https://github.com/apache/camel/tree/master/examples/camel-example-kafka
Java 1.8 Camel：2.21.0
错误：
Message History
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RouteId ProcessorId Processor Elapsed (ms)
[DirectToKafka ] [DirectToKafka ] [direct://kafkaStart ] [ 60017]
[DirectToKafka ] [to1 ] [kafka:{{producer.topic}} ] [ 60013]
Stacktrace
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org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
Exception in thread "main" org.apache.camel.CamelExecutionException: Exception occurred during execution on the exchange: Exchange[ID-host-1513537490104-0-1]
at org.apache.camel.util.ObjectHelper.wrapCamelExecutionException(ObjectHelper.java:1846)
at org.apache.camel.util.ExchangeHelper.extractResultBody(ExchangeHelper.java:713)
at org.apache.camel.impl.DefaultProducerTemplate.extractResultBody(DefaultProducerTemplate.java:515)
at org.apache.camel.impl.DefaultProducerTemplate.extractResultBody(DefaultProducerTemplate.java:511)
at org.apache.camel.impl.DefaultProducerTemplate.sendBodyAndHeaders(DefaultProducerTemplate.java:259)
at org.apache.camel.impl.DefaultProducerTemplate.sendBodyAndHeaders(DefaultProducerTemplate.java:253)
at org.apache.camel.example.kafka.MessagePublisherClient.main(MessagePublisherClient.java:91)
Caused by: org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.