We Keep Coding

java.lang.NoClassDefFoundError: org/slf4j/Logger

I am trying to run a project that uses a Logger class. Trying to do so causes the exception below. The compiler is looking for Logger at org/slf4j/Logger however in my Libraries it is located at org/apache/log4j (I am using IntelliJ). How can I fix this?
Exception in thread "main" java.lang.NoClassDefFoundError: org/slf4j/Logger
at org.apache.logging.slf4j.SLF4JLoggerContext.getLogger(SLF4JLoggerContext.java:42)
at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:455)
at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:441)
at activitystreamer.Client.<clinit>(Client.java:17)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:123)
Caused by: java.lang.ClassNotFoundException: org.slf4j.Logger
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 7 more

Kafka Utils wrong classpath: org.apache.kafka.common.utils.Utils

I'm attempting to make a very simple Kafka Producer and am currently following the producer example except my producer does not have a partitioner class.
After exporting required files into a jar I transfer them to my Linux image and try to run it.
I get this 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 org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58)
Caused by: java.lang.NoClassDefFoundError: org/apache/kafka/common/utils/Utils
at kafka.client.ClientUtils$$anonfun$parseBrokerList$1.apply(ClientUtils.scala:103)
at kafka.client.ClientUtils$$anonfun$parseBrokerList$1.apply(ClientUtils.scala:102)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:194)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:194)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:60)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:44)
at scala.collection.TraversableLike$class.map(TraversableLike.scala:194)
at scala.collection.mutable.ArrayBuffer.map(ArrayBuffer.scala:44)
at kafka.client.ClientUtils$.parseBrokerList(ClientUtils.scala:102)
at kafka.producer.BrokerPartitionInfo.<init>(BrokerPartitionInfo.scala:32)
at kafka.producer.async.DefaultEventHandler.<init>(DefaultEventHandler.scala:41)
at kafka.producer.Producer.<init>(Producer.scala:60)
at kafka.javaapi.producer.Producer.<init>(Producer.scala:26)
at producers.HelloWorldProducer.main(HelloWorldProducer.java:20)
... 5 more
Caused by: java.lang.ClassNotFoundException: org.apache.kafka.common.utils.Utils
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)
... 19 more
After looking at the kafka jar I see that the utils is its own package now and not located within common.
What would be the best way to solve this issue?

The answer ended up being real silly ... I needed to use the kafka-clients-0.8.2.0.jar instead.

Hadoop: ClassNotFoundException $Reduce

I've got a word count example class called by a Jetty server's handle method. The job is submitted with:
JobClient.runJob(conf);
Sadly, the JobTracker sees nothing, the job does not get submitted, but it finishes and creates output. I've found out, that I have to inject my configurations with:
conf.addResource(new Path("/usr/local/hadoop/conf/mapred-site.xml"));
After adding this line, the JobTracker gets the job, but it fails with the following exception:
INFO: Task Id : attempt_201312071601_0005_m_000000_1, Status : FAILED
java.lang.RuntimeException: java.lang.RuntimeException: java.lang.ClassNotFoundException: WC2$Reduce
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:889)
at org.apache.hadoop.mapred.JobConf.getCombinerClass(JobConf.java:1049)
at org.apache.hadoop.mapred.Task$CombinerRunner.create(Task.java:1385)
at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.<init>(MapTask.java:986)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:422)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:366)
at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1190)
at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: WC2$Reduce
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:857)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:881)
... 10 more
Caused by: java.lang.ClassNotFoundException: WC2$Reduce
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:270)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:810)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:855)
... 11 more
My combiner class is the same as the reducer class. I've downloaded the Hadoop WordCount example without modifications. Only the mentioned addResource.

ClassNotFoundException in java?

I am trying to run example from this particular site:
https://github.com/larsgeorge/hbase-book/tree/master/ch07
Now.. it compiles succesfully
But when I try to run an example, it gives me the following exception:
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:115)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:719)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:416)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)
at org.apache.hadoop.mapred.Child.main(Child.java:249)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:532)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:113)
... 7 more
Caused by: java.lang.NoClassDefFoundError: org/json/simple/parser/JSONParser
at mapreduce.ParseJson2$ParseMapper.<init>(ParseJson2.java:48)
... 12 more
Caused by: java.lang.ClassNotFoundException: org.json.simple.parser.JSONParser
at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
... 13 more
Now from the pom in this file, I can see that simple json is included but I am not sure why is it throwing this issue.?

I would say that the problem is that when run under map-reduce the jar you need is not in scope (i.e. not found). One way to fix that is to create a jar with all the dependencies and submit that as the job. Other options are to make sure it is available in each node and deploying the depdndecies to Hadoops' distribtued cache (but the first is the simplest - though it makes for slower job starts since the jar is bigger)

How to add OracleDriver to hadoop classpath while executing the job?

I'm using hadoop for processing a large amount of data from the database. I'm using oracle's jdbc driver to connect to Oracle DB and do the processing. But when i try to execute the hadoop job via bin/hadoop with the packaged JAR file, it's showing OracleDriver class not found. how do i fix this?
$ bin/hadoop jar ~/hadoop1.jar name.hadoop.Hadoop1 ~/output
Exception in thread "main" java.lang.RuntimeException: Error in configuring object
at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:93)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:64)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:117)
at org.apache.hadoop.mapred.JobConf.getInputFormat(JobConf.java:575)
at org.apache.hadoop.mapred.JobClient.writeOldSplits(JobClient.java:1051)
at org.apache.hadoop.mapred.JobClient.writeSplits(JobClient.java:1043)
at org.apache.hadoop.mapred.JobClient.access$700(JobClient.java:179)
at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:959)
at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:912)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1136)
at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:912)
at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:886)
at org.apache.hadoop.mapred.JobClient.runJob(JobClient.java:1323)
at name.shahalpk.poc.hadoop.Hadoop1.main(Hadoop1.java:73)
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:601)
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)
Caused by: 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:601)
at org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:88)
... 20 more
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
at org.apache.hadoop.mapred.lib.db.DBInputFormat.configure(DBInputFormat.java:271)
... 25 more
Caused by: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:186)
at org.apache.hadoop.mapred.lib.db.DBConfiguration.getConnection(DBConfiguration.java:123)
at org.apache.hadoop.mapred.lib.db.DBInputFormat.configure(DBInputFormat.java:266)
... 25 more

Add ojdbc5.jar into class path:
${JRE_HOME}\jre\lib\ext
Note:
${JRE_HOME} means JRE(Java Runtime Environment) Installed Directory; Like below
${JRE_HOME}=C:\Program Files\Java\jre6\

You can use the -libjars generic option to achieve this more easily, and it handles distribution of your jar to the cluster nodes too:
$ bin/hadoop jar ~/hadoop1.jar name.hadoop.Hadoop1 -libjars ojdbc5.jar ~/output
This does assume that your main class (name.hadoop.Hadoop1) is using the ToolRunner.run() method to launch your job:
public class Hadoop1 extends Configured implements Tool {
public static void main(String args[]) throws Exception {
ToolRunner.run(new Hadoop1(), args);
}
public int run(String args[]) {
JobConf job = new JobConf(getConf());
// rest of your job init code...
RunningJob rj = JobClient.runJob(job);
rj.waitForCompletion();
return rj.isSuccessful() ? 0 : 1;
}
}
(Hand typed code, apologises for any typos or compile errors)