Develop Reference

Spark- Exception in thread java.lang.NoSuchMethodError

I am trying to score a model from pmml file using pmml4s library. Every time I submit the job in Spark I get the following error:
20/05/13 23:30:10 ERROR SparkSubmit: org.apache.spark.sql.types.StructType.names().
[Ljava/lang/String;
java.lang.NoSuchMethodError: org.apache.spark.sql.types.StructType.names().
[Ljava/lang/String;
at org.pmml4s.spark.ScoreModel.transform(ScoreModel.scala:56)
at com.aexp.JavaPMML.main(JavaPMML.java:24)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.spark.deploy.JavaMainApplication.start(SparkApplication.scala:52)
Following is my code sample:
ScoreModel model = ScoreModel.fromFile(args[0]);
SparkConf conf = new SparkConf();
SparkSession spark = SparkSession.builder().config(conf).getOrCreate();
Dataset<?> df = spark.read().format("csv")
.option("header", "true")
.option("inferSchema", "true")
.load(args[1]);
Dataset<?> scoreDf = model.transform(df);
Following is the pom file that I am using:
<dependencies>
<dependency>
<groupId>org.pmml4s</groupId>
<artifactId>pmml4s-spark_2.11</artifactId>
<version>0.9.1</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-sql_2.11</artifactId>
<version>2.3.2</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.11</artifactId>
<version>2.3.2</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-mllib_2.11</artifactId>
<version>2.3.2</version>
</dependency>
</dependencies>
I have edited my pom file and made the spark version similar still I face the same issue. When I am using Scala, I am facing the same problem. Is there any dependency that I am missing?

Try to use same version of spark libraries. If spark versions are not matching we will be getting NoSuchMethodError issue in many places as those methods might have modified or removed in latest versions.

The error is caused by the PMML4S-Spark used the method names of StructType, which is introduced since Spark 2.4. Now it has been fixed in the latest PMML4S-Spark 0.9.5. Please, update your pom file to use the new version:
<dependency>
<groupId>org.pmml4s</groupId>
<artifactId>pmml4s-spark_2.11</artifactId>
<version>0.9.5</version>
</dependency>

Getting Error "java.lang.NoSuchMethodError: org.apache.kafka.clients.consumer.KafkaConsumer.assign" when tring to consume using flink's Kafka Consumer

I was trying to write a Kafka Consumer which consumes data from a topic. But whenever i try to run it i get the following error.
Exception in thread "main" org.apache.flink.runtime.client.JobExecutionException: Job execution failed.
at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$6.apply$mcV$sp(JobManager.scala:897)
at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$6.apply(JobManager.scala:840)
at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$6.apply(JobManager.scala:840)
at scala.concurrent.impl.Future$PromiseCompletingRunnable.liftedTree1$1(Future.scala:24)
at scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:24)
at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:39)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:415)
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: java.lang.NoSuchMethodError: org.apache.kafka.clients.consumer.KafkaConsumer.assign(Ljava/util/List;)V
at org.apache.flink.streaming.connectors.kafka.internal.KafkaConsumerCallBridge.assignPartitions(KafkaConsumerCallBridge.java:39)
at org.apache.flink.streaming.connectors.kafka.internal.KafkaConsumerThread.reassignPartitions(KafkaConsumerThread.java:391)
at org.apache.flink.streaming.connectors.kafka.internal.KafkaConsumerThread.run(KafkaConsumerThread.java:229)
The Java Class is:
import org.apache.flink.api.java.utils.ParameterTool;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer09;
import org.apache.flink.streaming.util.serialization.SimpleStringSchema;
public class KafkaConsumer {
public static void main(String[] args) throws Exception{
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
ParameterTool parameterTool = ParameterTool.fromArgs(args);
DataStream<String> stream = env.addSource(new FlinkKafkaConsumer09<String>("rdf-new", new SimpleStringSchema(), parameterTool.getProperties()));
stream.print();
env.execute();
}}
I had created a standalone project (with its own pom) in intellij with the same code and it was working fine but since i required the code in another project i created a new maven module in the already existing project and then tried running it and now it is showing me this error.
The dependencies in the pom.xml for the maven module is:
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<flink.version>1.4.2</flink.version>
<java.version>1.8</java.version>
<scala.binary.version>2.11</scala.binary.version>
<maven.compiler.source>${java.version}</maven.compiler.source>
<maven.compiler.target>${java.version}</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-java</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_2.11</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-clients_2.11</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-core</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-kafka-0.9_2.11</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.7</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-cep_2.11</artifactId>
<version>${flink.version}</version>
</dependency>
</dependencies>
The only thing i noticed was inside the maven module i was getting the KafkaVersion as 1.1.0, but the pom has the KafkaConnector "flink-connector-kafka-0.9_2.11"
2018-05-18 11:14:56,105 - AbstractConfig [WARN] - ConsumerConfig - The configuration 'zookeeper.connect' was supplied but isn't a known config.
2018-05-18 11:14:56,105 - AppInfoParser$AppInfo [INFO] - AppInfoParser - Kafka version : 1.1.0
2018-05-18 11:14:56,105 - AppInfoParser$AppInfo [INFO] - AppInfoParser - Kafka commitId : fdcf75ea326b8e07
While in the standalone project (where the consumer properly works) the Kafka Version is 0.9.0.1.
11:32:19,537 WARN org.apache.kafka.clients.consumer.ConsumerConfig - The configuration zookeeper.connect = localhost:2181 was supplied but isn't a known config.
11:32:19,537 INFO org.apache.kafka.common.utils.AppInfoParser - Kafka version : 0.9.0.1
11:32:19,538 INFO org.apache.kafka.common.utils.AppInfoParser - Kafka commitId : 23c69d62a0cabf06
It would be a huge help if someone can tell me what could be the issue? It could be because of dependencies in the pom file but in the standalone project also its the same dependencies that i had given in.
Thanks in advance.

As you already figured out the problem is that in your module the kafka version (1.0) doesn't match the version that flink connector is expecting (0.9).
You can do:
mvn dependency:tree
on the command line to figure out where the kafka clients dependency version is coming from.
In your module's pom you can add a dependencyManagement section to override the kafka client library dependency version to the one you need, like so:
<dependencyManagement>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>0.9.0.1</version>
</dependency>
</dependencyManagement>

Spark on HBase exception class not found (JAVA)

Im trying to communicate with hbase using spark. I´m using this code below:
SparkConf sparkConf = new SparkConf().setAppName("HBaseRead");
JavaSparkContext jsc = new JavaSparkContext(sparkConf);
Configuration conf = HBaseConfiguration.create();
conf.addResource(new Path("/etc/hbase/conf/core-site.xml"));
conf.addResource(new Path("/etc/hbase/conf/hbase-site.xml"));
JavaHBaseContext hbaseContext = new JavaHBaseContext(jsc, conf);
Scan scan = new Scan();
scan.setCaching(100);
JavaRDD<Tuple2<ImmutableBytesWritable, Result>> hbaseRdd = hbaseContext.hbaseRDD(TableName.valueOf("climate"), scan);
System.out.println("Number of Records found : " + hbaseRdd.count());
If I execute this, I get the following error:
Exception in thread "dag-scheduler-event-loop" java.lang.NoClassDefFoundError: org/apache/hadoop/hbase/regionserver/StoreFileWriter
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
at java.lang.Class.getDeclaredMethod(Class.java:2128)
at java.io.ObjectStreamClass.getPrivateMethod(ObjectStreamClass.java:1475)
at java.io.ObjectStreamClass.access$1700(ObjectStreamClass.java:72)
at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:498)
at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:472)
at java.security.AccessController.doPrivileged(Native Method)
at java.io.ObjectStreamClass.<init>(ObjectStreamClass.java:472)
at java.io.ObjectStreamClass.lookup(ObjectStreamClass.java:369)
...
I did not find any solution via google. Has anyone an idea?
--------edit--------
I´m using maven. My Pom looks like:
<dependencies>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-server</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>org.sharegov</groupId>
<artifactId>mjson</artifactId>
<version>1.4.1</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.10</artifactId>
<version>1.5.2</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-sql_2.10</artifactId>
<version>1.5.2</version>
</dependency>
<dependency>
<groupId>com.databricks</groupId>
<artifactId>spark-csv_2.10</artifactId>
<version>1.5.0</version>
</dependency>
<dependency>
<groupId>com.databricks</groupId>
<artifactId>spark-xml_2.10</artifactId>
<version>0.3.5</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-spark</artifactId>
<version>2.0.0-SNAPSHOT</version>
</dependency>
</dependencies>
Im building my application with dependencies using the maven-assembly-plugin

You are getting the NoClassDefFoundError, because spark is not able to find hbase jars in the classpath, you need to supply the required jars to spark-submit explicitly using --jars parameter while launching job:
${SPARK_HOME}/bin/spark-submit \
--jars ${..add hbase jars comma separated...}
--class ....
.........

HBase Java API for HBaseTable creation shows Error

I am a beginner in Hadoop and Hbase. I am getting error when I try to create an HBase Table using Java API. My project is a maven Project. I am using cloudera machine for running my application. Code sample and error and POM.xml is given below
public static void main(String[] args) throws IOException {
// Instantiating configuration class
Configuration con = HBaseConfiguration.create();
HBaseAdmin admin = new HBaseAdmin(con);
// Instantiating table descriptor class
HTableDescriptor tableDescriptor = new HTableDescriptor(TableName.valueOf("empdata"));
// Adding column families to table descriptor
tableDescriptor.addFamily(new HColumnDescriptor("personal"));
tableDescriptor.addFamily(new HColumnDescriptor("official"));
// Execute the table through admin
admin.createTable(tableDescriptor);
System.out.println(" Table created ");
}
Command I am giving like this :
-bash-4.1$ hadoop jar HBaseTableCreation-1.0-SNAPSHOT.jar com.HBaseTable
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/hbase/HBaseConfiguration
at com.Feathersoft.HBaseTable.main(HBaseTable.java:17)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.hbase.HBaseConfiguration
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 6 more
-bash-4.1$
POM.xml dependancies
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-common</artifactId>
<version>0.98.8-hadoop2</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-server</artifactId>
<version>0.95.0</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-shell</artifactId>
<version>0.98.8-hadoop2</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-protocol</artifactId>
<version>0.98.8-hadoop2</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-thrift</artifactId>
<version>0.98.8-hadoop2</version>
</dependency>
<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>com.google.protobuf</groupId>
<artifactId>protobuf-java</artifactId>
<version>2.4.0a</version>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>11.0.2</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-client</artifactId>
<version>2.0.0-cdh4.2.0</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-client</artifactId>
<version>0.98.8-hadoop2</version>
</dependency>
How can I set classpath in Cloudera Machine. I am not so much familiar in Linux.
Can any one help, It would be great ....

Kafka Quickstart: What Dependencies do I need?

I am working through the kafka quickstart:
http://kafka.apache.org/07/quickstart.html
and the basic Consumer Group example:
https://cwiki.apache.org/confluence/display/KAFKA/Consumer+Group+Example
I have coded up the Consumer and ConsumerThreadPool as above:
import kafka.consumer.KafkaStream;
import kafka.consumer.ConsumerIterator;
public class Consumer implements Runnable {
private KafkaStream m_stream;
private Integer m_threadNumber;
public Consumer(KafkaStream a_stream, Integer a_threadNumber) {
m_threadNumber = a_threadNumber;
m_stream = a_stream;
}
public void run() {
ConsumerIterator<byte[], byte[]> it = m_stream.iterator();
while (it.hasNext()) {
System.out.println("Thread " + m_threadNumber + ": " + new String(it.next().message()));
}
System.out.println("Shutting down Thread: " + m_threadNumber);
}
}
A couple of other facets: I am using spring to manage my zookeeper:
import javax.inject.Named;
import java.util.Properties;
import kafka.consumer.ConsumerConfig;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
#Configuration
#ComponentScan("com.truecar.inventory.worker.core")
public class AppConfig {
#Bean
#Named("consumerConfig")
private static ConsumerConfig createConsumerConfig() {
String zookeeperAddress = "127.0.0.1:2181";
String groupId = "inventory";
Properties props = new Properties();
props.put("zookeeper.connect", zookeeperAddress);
props.put("group.id", groupId);
props.put("zookeeper.session.timeout.ms", "400");
props.put("zookeeper.sync.time.ms", "200");
props.put("auto.commit.interval.ms", "1000");
return new ConsumerConfig(props);
}
}
And I am compiling with Maven and the OneJar Maven plugin. However, I compile and then run the resulting one jar I get the following error:
Aug 26, 2013 6:15:41 PM org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider registerDefaultFilters
INFO: JSR-330 'javax.inject.Named' annotation found and supported for component scanning
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.simontuffs.onejar.Boot.run(Boot.java:340)
at com.simontuffs.onejar.Boot.main(Boot.java:166)
Caused by: java.lang.NoClassDefFoundError: scala/ScalaObject
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:792)
at com.simontuffs.onejar.JarClassLoader.defineClass(JarClassLoader.java:803)
at com.simontuffs.onejar.JarClassLoader.findClass(JarClassLoader.java:710)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at com.simontuffs.onejar.JarClassLoader.loadClass(JarClassLoader.java:630)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2521)
at java.lang.Class.getDeclaredMethods(Class.java:1845)
at org.springframework.core.type.StandardAnnotationMetadata.getAnnotatedMethods(StandardAnnotationMetadata.java:180)
at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:222)
at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:165)
at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:140)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:282)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:223)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:630)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:461)
at org.springframework.context.annotation.AnnotationConfigApplicationContext.<init>(AnnotationConfigApplicationContext.java:73)
at com.truecar.inventory.worker.core.consumer.ConsumerThreadPool.<clinit>(ConsumerThreadPool.java:31)
at com.truecar.inventory.worker.core.application.Starter.main(Starter.java:20)
... 6 more
Caused by: java.lang.ClassNotFoundException: scala.ScalaObject
at com.simontuffs.onejar.JarClassLoader.findClass(JarClassLoader.java:713)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at com.simontuffs.onejar.JarClassLoader.loadClass(JarClassLoader.java:630)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 27 more
Now, I know little about Kafka, and nothing about Scala. How do I fix this? What should i try next? Is this a known issue? Do I need other dependencies? Here is the kafka version in my pom.xml:
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka_2.9.2</artifactId>
<version>0.8.0-beta1</version>
</dependency>
Update: I contacted the Kafka dev mailing list, and they let me know some specific version requirements for the scala dependencies. However, there is also an undocumented log4j dependency, which results in another runtime, not compile time, exception.
Exception in thread "main" java.lang.reflect.InvocationTargetException
Caused by: java.lang.NoSuchMethodError: ch.qos.logback.classic.Logger.filterAndLog(Ljava/lang/String;Lorg/slf4j/Marker;Lch/qos/logback/classic/Level;Ljava/lang/String;[Ljava/lang/Object;Ljava/lang/Throwable;)V
at org.apache.log4j.Category.log(Category.java:333)
at org.apache.commons.logging.impl.Log4JLogger.debug(Log4JLogger.java:177)
Another Update:
I found the correct log4j dependency:
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
But now I am met with an even more cryptic runtime exception:
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.simontuffs.onejar.Boot.run(Boot.java:340)
at com.simontuffs.onejar.Boot.main(Boot.java:166)
Caused by: java.lang.NoClassDefFoundError: org/I0Itec/zkclient/IZkStateListener
at kafka.javaapi.consumer.ZookeeperConsumerConnector.<init>(ZookeeperConsumerConnector.scala:64)
at kafka.javaapi.consumer.ZookeeperConsumerConnector.<init>(ZookeeperConsumerConnector.scala:66)
at kafka.consumer.Consumer$.createJavaConsumerConnector(ConsumerConnector.scala:100)
at kafka.consumer.Consumer.createJavaConsumerConnector(ConsumerConnector.scala)
At this point I got the WTF kind of feeling. So I added another dependency:
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.3</version>
</dependency>
But this exposed yet another runtime exception:
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.simontuffs.onejar.Boot.run(Boot.java:340)
at com.simontuffs.onejar.Boot.main(Boot.java:166)
Caused by: java.lang.NoClassDefFoundError: com/yammer/metrics/core/Gauge
at kafka.consumer.ZookeeperConsumerConnector.createFetcher(ZookeeperConsumerConnector.scala:146)
at kafka.consumer.ZookeeperConsumerConnector.<init>(ZookeeperConsumerConnector.scala:113)
at kafka.javaapi.consumer.ZookeeperConsumerConnector.<init>(ZookeeperConsumerConnector.scala:64)
at kafka.javaapi.consumer.ZookeeperConsumerConnector.<init>(ZookeeperConsumerConnector.scala:66)
at kafka.consumer.Consumer$.createJavaConsumerConnector(ConsumerConnector.scala:100)
at kafka.consumer.Consumer.createJavaConsumerConnector(ConsumerConnector.scala)
I am hoping to be able to get this baby example up and running, but maybe this is the price to pay for using beta products? Maybe I should switch to Apache Active MQ. But that sounds less fun. Am I missing something?

The problem is that kafka beta was built in a way that pom generated with a jar isn't valid and maven could not recognize it and parse properly, thus fetching transitive dependencies. We've managed to mitigate this problem by enlisting all of the dependencies from that pom (scala, zk, etc) in our pom definition. We're waiting for next beta builds of kafka, in which problem will be fixed.
Full dependencies list is below. Note that you have to change scala version dependency accordingly to the postfix of your kafka artifact.
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.8.0</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.15</version>
<exclusions>
<exclusion>
<groupId>com.sun.jmx</groupId>
<artifactId>jmxri</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jdmk</groupId>
<artifactId>jmxtools</artifactId>
</exclusion>
<exclusion>
<groupId>javax.jms</groupId>
<artifactId>jms</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>net.sf.jopt-simple</groupId>
<artifactId>jopt-simple</artifactId>
<version>3.2</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.6.4</version>
</dependency>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-compiler</artifactId>
<version>2.8.0</version>
</dependency>
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.3</version>
</dependency>
<dependency>
<groupId>com.yammer.metrics</groupId>
<artifactId>metrics-core</artifactId>
<version>2.2.0</version>
</dependency>
<dependency>
<groupId>com.yammer.metrics</groupId>
<artifactId>metrics-annotation</artifactId>
<version>2.2.0</version>
</dependency>
<dependency>
<groupId>org.easymock</groupId>
<artifactId>easymock</artifactId>
<version>3.0</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.scalatest</groupId>
<artifactId>scalatest</artifactId>
<version>1.2</version>
<scope>test</scope>
</dependency>
As for the
Maybe I should switch to Apache Active MQ. But that sounds less fun.
Am I missing something?
Well, don't you forget that this is the beta release? Some bad things are happening, indeed, but currently we're running kafka 0.7 without any efforts.

I found this configuration of dependencies to be functional:
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.2.4.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.2.4.RELEASE</version>
</dependency>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka_2.9.2</artifactId>
<version>0.8.0-beta1</version>
</dependency>
<dependency>
<groupId>javax.inject</groupId>
<artifactId>javax.inject</artifactId>
<version>1</version>
</dependency>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.9.2</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.3</version>
</dependency>
<dependency>
<groupId>com.yammer.metrics</groupId>
<artifactId>metrics-core</artifactId>
<version>2.2.0</version>
</dependency>
</dependencies>

This seems to work :
$ git clone https://github.com/buildlackey/cep
$ cd cep/kafka-0.8.x
$ mvn package
$ mvn exec:java -Dexec.mainClass=TestKafkaProducer
(via where can I find maven repository for kafka? )