Hi all,
I tried running the wordcount example on oozie and i'm getting the
following exception on my hadoop log:
ERROR org.apache.hadoop.security.UserGroupInformation:
PriviledgedActionException as:cloudera (auth:SIMPLE)
cause:java.io.IOException: Type mismatch in key from map: expected
org.apache.hadoop.io.LongWritable, recieved org.apache.hadoop.io.Text
2012-05-22 18:58:27,832 WARN org.apache.hadoop.mapred.Child: Error running
child
java.io.IOException: Type mismatch in key from map: expected
org.apache.hadoop.io.LongWritable, recieved org.apache.hadoop.io.Text
at
org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:871)
at
org.apache.hadoop.mapred.MapTask$OldOutputCollector.collect(MapTask.java:499)
at WordCount$Map.map(WordCount.java:22)
at WordCount$Map.map(WordCount.java:12)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:391)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:325)
at org.apache.hadoop.mapred.Child$4.run(Child.java:270)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1177)
at org.apache.hadoop.mapred.Child.main(Child.java:264)
WordCount.java is copied verbatim from the apache mapreduce tutorial. I
removed the combiner that solved the problem for some people over at
stackoverflow, but i'm still getting the error. I ran the same jar in
hadoop and got the correct output with no error. Posting WordCount.java for
completeness.
import java.io.IOException;
import java.util.*;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.util.*;
public class WordCount {
public static class Map extends MapReduceBase implements
Mapper<LongWritable, Text, Text, IntWritable> {
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
public void map(LongWritable key, Text value,
OutputCollector<Text, IntWritable> output, Reporter reporter) throws
IOException {
String line = value.toString();
System.out.println("here"+"\t"+ line + "\t" + key);
StringTokenizer tokenizer = new StringTokenizer(line);
while (tokenizer.hasMoreTokens()) {
word.set(tokenizer.nextToken());
output.collect(word, one);
}
}
}
public static class Reduce extends MapReduceBase implements
Reducer<Text, IntWritable, Text, IntWritable> {
public void reduce(Text key, Iterator<IntWritable> values,
OutputCollector<Text, IntWritable> output, Reporter reporter) throws
IOException {
int sum = 0;
while (values.hasNext()) {
sum += values.next().get();
}
output.collect(key, new IntWritable(sum));
}
}
public static void main(String[] args) throws Exception {
JobConf conf = new JobConf(WordCount.class);
//conf.setJobName("wordcount");
//conf.setJar("wordcount.jar");
conf.setOutputKeyClass(Text.class);
conf.setOutputValueClass(IntWritable.class);
conf.setMapperClass(Map.class);
conf.setReducerClass(Reduce.class);
conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);
//FileInputFormat.setInputPaths(conf, new Path(args[0]));
//FileOutputFormat.setOutputPath(conf, new Path(args[1]));
JobClient.runJob(conf);
}
}
Note that if I change mapper to map and reducer to reduce , I don't get
the error but I get wrong output. I checked the input given to the mapper
and that is apparently empty. And here is my workflow.xml. :
<workflow-app name='wordcount-wf' xmlns="uri:oozie:workflow:0.1">
<start to='wordcount'/>
<action name='wordcount'>
<map-reduce>
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<prepare>
</prepare>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
<property>
<name>mapred.mapper.class</name>
<value>WordCount$Map</value>
</property>
<property>
<name>mapred.reducer.class</name>
<value>WordCount$Reduce</value>
</property>
<property>
<name>mapred.input.dir</name>
<value>${inputDir}</value>
</property>
<property>
<name>mapred.output.dir</name>
<value>${outputDir}</value>
</property>
</configuration>
</map-reduce>
<ok to='end'/>
<error to='end'/>
</action>
<kill name='kill'>
<message>${wf:errorCode("wordcount")}</message>
</kill>
<end name='end'/>
</workflow-app>
I'm running oozie and hadoop on a single VM taken from cloudera.
oozie version:
Oozie client build version: 2.3.2-cdh3u4
hadoop version:
Subversion file:///data/1/tmp/topdir/BUILD/hadoop-0.20.2-cdh3u4 -r
214dd731e3bdb687cb55988d3f47dd9e248c5690
Compiled by root on Mon May 7 14:03:02 PDT 2012
>From source with checksum a60c9795e41a3248b212344fb131c12c
