anchor.diff:          exchange.getIn().setBody("test event");
   })
   .to("vertx-kafka:test_topic?bootstrapServers=kafka9092")
  -```
  +----
   
   Also, the component supports as well *aggregation* of messages by sending events as *iterable* of either Exchanges/Messages or normal data (e.g: list of Strings). For example:
  -```
  +
  +[source,java]
  +----
   from("direct:start")
   .process(exchange -> {
           final List<String> messages = new LinkedList<>();
  
positive.code: 
  Here is the minimal route you need in order to write messages to Kafka.
  
  ```
  from("direct")
      .process(exchange -> {
          // set kafka header
  
negative.code:         System.out.println(headerBuffer.getDouble(0); // it will print 2.0
  })
  .to("direct)
  ----
  
  By default all headers are being filtered by `KafkaHeaderFilterStrategy`.
  Strategy filters out headers which start with `Camel` or `org.apache.camel` prefixes.
  