应用程序正在从一个Kafka主题中读取消息，并且在MongoDB中存储并进行一些验证后，它正在写入另一个主题。在这里，我面临着应用程序进入无限循环的问题。 我的代码如下：
int ver(char* v)在上面的代码中，Hosts zkHosts = new ZkHosts("localhost:2181");
String zkRoot = "/brokers/topics" ;
String clientRequestID = "reqtest";
String clientPendingID = "pendtest";
SpoutConfig kafkaRequestConfig = new SpoutConfig(zkHosts,"reqtest",zkRoot,clientRequestID);
SpoutConfig kafkaPendingConfig = new SpoutConfig(zkHosts,"pendtest",zkRoot,clientPendingID);
kafkaRequestConfig.scheme = new SchemeAsMultiScheme(new StringScheme());
kafkaPendingConfig.scheme = new SchemeAsMultiScheme(new StringScheme());
KafkaSpout kafkaRequestSpout = new KafkaSpout(kafkaRequestConfig);
KafkaSpout kafkaPendingSpout = new KafkaSpout(kafkaPendingConfig);
MongoBolt mongoBolt = new MongoBolt() ;
DeviceFilterBolt deviceFilterBolt = new DeviceFilterBolt() ;
KafkaRequestBolt kafkaReqBolt = new KafkaRequestBolt() ;
abc1DeviceBolt abc1DevBolt = new abc1DeviceBolt() ;
DefaultTopicSelector defTopicSelector = new DefaultTopicSelector(xyzKafkaTopic.RESPONSE.name()) ;
KafkaBolt kafkaRespBolt = new KafkaBolt()
.withTopicSelector(defTopicSelector)
.withTupleToKafkaMapper(new FieldNameBasedTupleToKafkaMapper()) ;
TopologyBuilder topoBuilder = new TopologyBuilder();
topoBuilder.setSpout(xyzComponent.KAFKA_REQUEST_SPOUT.name(), kafkaRequestSpout);
topoBuilder.setSpout(xyzComponent.KAFKA_PENDING_SPOUT.name(), kafkaPendingSpout);
topoBuilder.setBolt(xyzComponent.KAFKA_PENDING_BOLT.name(),
deviceFilterBolt, 1)
.shuffleGrouping(xyzComponent.KAFKA_PENDING_SPOUT.name()) ;
topoBuilder.setBolt(xyzComponent.abc1_DEVICE_BOLT.name(),
abc1DevBolt, 1)
.shuffleGrouping(xyzComponent.KAFKA_PENDING_BOLT.name(),
xyzDevice.abc1.name()) ;
topoBuilder.setBolt(xyzComponent.MONGODB_BOLT.name(),
mongoBolt, 1)
.shuffleGrouping(xyzComponent.abc1_DEVICE_BOLT.name(),
xyzStreamID.KAFKARESP.name());
topoBuilder.setBolt(xyzComponent.KAFKA_RESPONSE_BOLT.name(),
kafkaRespBolt, 1)
.shuffleGrouping(xyzComponent.abc1_DEVICE_BOLT.name(),
xyzStreamID.KAFKARESP.name());
Config config = new Config() ;
config.setDebug(true);
config.setNumWorkers(1);
Properties props = new Properties();
props.put("metadata.broker.list", "localhost:9092");
props.put("serializer.class", "kafka.serializer.StringEncoder");
props.put("request.required.acks", "1");
config.put(KafkaBolt.KAFKA_BROKER_PROPERTIES, props);
LocalCluster cluster = new LocalCluster();
try{
cluster.submitTopology("demo", config, topoBuilder.createTopology());
}
正在将数据写入主题。
KAFKA_RESPONSE_BOLT通过发送如下数据来提供此abc1_DEVICE_BOLT
KAFKA_RESPONSE_BOLT答案 0 :(得分：1)
长期以来，我一直被同样的问题困扰，答案非常简单......你不会相信它。
据我了解，KafkaBolt的实现必须接收元组的字段名称为“message”，无论它是Bolt还是Spout。所以你必须对你的代码做一些修改，我没有仔细看过。（但我相信这会有所帮助！）