apache-kafka - KafkaSpout 为 log4j 抛出 NoClassDefFoundError

Question

出于某种原因，当我尝试在 Storm 集群上运行拓扑时出现以下错误:

java.lang.NoClassDefFoundError: Could not initialize class org.apache.log4j.Log4jLoggerFactory
  at org.apache.log4j.Logger.getLogger(Logger.java:39)
  at kafka.utils.Logging$class.logger(Logging.scala:24)
  at kafka.consumer.SimpleConsumer.logger$lzycompute(SimpleConsumer.scala:30)
  at kafka.consumer.SimpleConsumer.logger(SimpleConsumer.scala:30)
  at kafka.utils.Logging$class.info(Logging.scala:67)
  at kafka.consumer.SimpleConsumer.info(SimpleConsumer.scala:30)
  at kafka.consumer.SimpleConsumer.liftedTree1$1(SimpleConsumer.scala:75)
  at kafka.consumer.SimpleConsumer.kafka$consumer$SimpleConsumer$$sendRequest(SimpleConsumer.scala:69)
  at kafka.consumer.SimpleConsumer.getOffsetsBefore(SimpleConsumer.scala:128)
  at kafka.javaapi.consumer.SimpleConsumer.getOffsetsBefore(SimpleConsumer.scala:79)
  at storm.kafka.KafkaUtils.getOffset(KafkaUtils.java:77)
  at storm.kafka.KafkaUtils.getOffset(KafkaUtils.java:67)
  at storm.kafka.PartitionManager.<init>(PartitionManager.java:83)
  at storm.kafka.ZkCoordinator.refresh(ZkCoordinator.java:98)
  at storm.kafka.ZkCoordinator.getMyManagedPartitions(ZkCoordinator.java:69)
  at storm.kafka.KafkaSpout.nextTuple(KafkaSpout.java:135)
  at backtype.storm.daemon.executor$fn__3373$fn__3388$fn__3417.invoke(executor.clj:565)
  at backtype.storm.util$async_loop$fn__464.invoke(util.clj:463) at clojure.lang.AFn.run(AFn.java:24)
  at java.lang.Thread.run(Thread.java:745)cg

问题是什么以及如何解决？

以下是我包含的依赖项:

 <dependencies>
    <dependency>
        <groupId>org.apache.storm</groupId>
        <artifactId>storm-core</artifactId>
        <version>0.9.5</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.kafka</groupId>
        <artifactId>kafka_2.10</artifactId>
        <version>0.8.2-beta</version>
    </dependency>
    <dependency>
        <groupId>org.apache.storm</groupId>
        <artifactId>storm-kafka</artifactId>
        <version>0.9.5</version>
    </dependency>
    <dependency>
        <groupId>org.codehaus.jackson</groupId>
        <artifactId>jackson-mapper-asl</artifactId>
        <version>1.9.11</version>
    </dependency>
    <dependency>
        <groupId>org.java-websocket</groupId>
        <artifactId>Java-WebSocket</artifactId>
        <version>1.3.0</version>
    </dependency>
    <dependency>
        <groupId>org.twitter4j</groupId>
        <artifactId>twitter4j-core</artifactId>
        <version>[3.0,)</version>
    </dependency>
    <dependency>
        <groupId>org.twitter4j</groupId>
        <artifactId>twitter4j-stream</artifactId>
        <version>[3.0,)</version>
    </dependency>
</dependencies>

Answer 1

问题是您应该通过以下方式包含 Kafka:

   <dependency>
        <groupId>org.apache.kafka</groupId>
        <artifactId>kafka_2.10</artifactId>
        <version>0.8.1.1</version>
        <exclusions>
            <exclusion>
                <groupId>org.apache.zookeeper</groupId>
                <artifactId>zookeeper</artifactId>
            </exclusion>
            <exclusion>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

出于以下原因:

Note that the ZooKeeper and log4j dependencies are excluded to prevent version conflicts with Storm's dependencies.