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From Rahul Singh <smart.rahul.i...@gmail.com>
Subject Re: Re: Hadoop NoClassDefFoundError
Date Wed, 16 Apr 2014 08:14:08 GMT
When i unzip my jar.. i get the class files inside the package hirarchy
while in your case all files are lying outside? are you  sure your jar was
properly created?


On Wed, Apr 16, 2014 at 1:21 PM, laozhao0@sina.cn <laozhao0@sina.cn> wrote:

> This is the result .
> /home/laozhao0 $ unzip -l myjob.jar
> Archive: /home/laozhao0/myjob.jar
> Length Date Time Name
> --------- ---------- ----- ----
> 0 04-15-2014 14:54 META-INF/
> 71 04-15-2014 14:54 META-INF/MANIFEST.MF
> 1300 04-15-2014 14:54 MyJob$MapClass.class
> 1628 04-15-2014 14:54 MyJob$Reduce.class
> 2160 04-15-2014 14:54 MyJob.class
> --------- -------
> 5159 5 files
>
> ------------------------------
> laozhao0@sina.cn
>
>
> *From:* Stanley Shi <sshi@gopivotal.com>
> *Date:* 2014-04-16 10:25
> *To:* user@hadoop.apache.org
> *Subject:* Re: Re: Hadoop NoClassDefFoundError
> can do you an "unzip -l myjob.jar" to see if your jar file has the correct
> hierarchy?
>
> Regards,
> *Stanley Shi,*
>
>
>
> On Tue, Apr 15, 2014 at 6:53 PM, laozhao0@sina.cn <laozhao0@sina.cn>wrote:
>
>> Thank you for your advice . When i user your command , i get the below
>> error info .
>> $ hadoop jar myjob.jar myjob.MyJob input output
>> Exception in thread "main" java.lang.ClassNotFoundException: myjob.MyJob
>> 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 java.lang.ClassLoader.loadClass(ClassLoader.java:356)
>> at java.lang.Class.forName0(Native Method)
>> at java.lang.Class.forName(Class.java:264)
>> at org.apache.hadoop.util.RunJar.main(RunJar.java:149)
>>
>> ------------------------------
>>
>>
>> *From:* Azuryy Yu <azuryyyu@gmail.com>
>> *Date:* 2014-04-15 16:14
>> *To:* user@hadoop.apache.org
>> *Subject:* Re: Hadoop NoClassDefFoundError
>> Please use: hadoop jar myjob.jar myjob.MyJob input output
>>
>>
>> On Tue, Apr 15, 2014 at 3:06 PM, laozhao0@sina.cn <laozhao0@sina.cn>wrote:
>>
>>> Hello EveryOne:
>>>     I am new to hadoop,and i am reading Hadoop in action.
>>> When i tried to run a demo from this book,I got a problem and could not
>>> find answer from the net. Can you help me on this ?
>>>
>>> below is the error info :
>>>
>>>   $ hadoop jar myjob.jar MyJob input output
>>> Exception in thread "main" java.lang.NoClassDefFoundError: MyJob (wrong
>>> name: myjob/MyJob)
>>> at java.lang.ClassLoader.defineClass1(Native Method)
>>> at java.lang.ClassLoader.defineClass(ClassLoader.java:791)
>>> at
>>> java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
>>> at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
>>> at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
>>> at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
>>> 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 java.lang.ClassLoader.loadClass(ClassLoader.java:356)
>>> at java.lang.Class.forName0(Native Method)
>>> at java.lang.Class.forName(Class.java:264)
>>> at org.apache.hadoop.util.RunJar.main(RunJar.java:149)
>>>
>>> and this is the command that i compile the .java , I compiled in Win7
>>> and ran on ubuntu .
>>>
>>>
>>> below is MyJob.java
>>>
>>> package myjob;
>>>
>>> import java.io.IOException;
>>> import java.util.Iterator;
>>>
>>> import org.apache.hadoop.conf.Configuration;
>>> import org.apache.hadoop.conf.Configured;
>>> import org.apache.hadoop.fs.Path;
>>> import org.apache.hadoop.io.Text;
>>> import org.apache.hadoop.mapred.FileInputFormat;
>>> import org.apache.hadoop.mapred.FileOutputFormat;
>>> import org.apache.hadoop.mapred.JobClient;
>>> import org.apache.hadoop.mapred.JobConf;
>>> import org.apache.hadoop.mapred.KeyValueTextInputFormat;
>>> import org.apache.hadoop.mapred.MapReduceBase;
>>> import org.apache.hadoop.mapred.Mapper;
>>> import org.apache.hadoop.mapred.OutputCollector;
>>> import org.apache.hadoop.mapred.Reducer;
>>> import org.apache.hadoop.mapred.Reporter;
>>> import org.apache.hadoop.mapred.TextOutputFormat;
>>> import org.apache.hadoop.util.Tool;
>>> import org.apache.hadoop.util.ToolRunner;
>>>
>>> public class MyJob extends Configured implements Tool{
>>>
>>> @Override
>>> public int run(String[] args) throws Exception {
>>> Configuration conf = getConf();
>>> JobConf job = new JobConf(conf,MyJob.class);
>>> Path in = new Path(args[0]);
>>> Path out = new Path(args[1]);
>>> FileInputFormat.setInputPaths(job, in);
>>> FileOutputFormat.setOutputPath(job, out);
>>> job.setJobName("MyJob");
>>> job.setJarByClass(MyJob.class);
>>> job.setMapperClass(MapClass.class);
>>> job.setReducerClass(Reduce.class);
>>>
>>> job.setInputFormat(KeyValueTextInputFormat.class);
>>> job.setOutputFormat(TextOutputFormat.class);
>>> job.setOutputKeyClass(Text.class);
>>> job.setOutputValueClass(Text.class);
>>> job.set("key.value.separator.in.input.line",",");
>>> JobClient.runJob(job);
>>> return 0;
>>> }
>>>
>>> public static class MapClass extends MapReduceBase implements
>>> Mapper<Text,Text,Text,Text>{
>>>
>>> @Override
>>> public void map(Text key, Text value, OutputCollector<Text, Text>
>>> output,
>>> Reporter reporter) throws IOException {
>>> output.collect(value, key);
>>> }
>>> }
>>>
>>> public static class Reduce extends MapReduceBase implements
>>> Reducer<Text,Text,Text,Text>{
>>>
>>> @Override
>>> public void reduce(Text key, Iterator<Text> values,
>>> OutputCollector<Text, Text> output, Reporter reporter)
>>> throws IOException {
>>> String csv = "";
>>> while(values.hasNext()){
>>> if(csv.length() > 0)
>>> csv += ",";
>>> csv += values.next().toString();
>>> }
>>> }
>>> }
>>>
>>> public static void main(String[] args) throws Exception {
>>> int res = ToolRunner.run(new Configuration(), new MyJob(), args);
>>> System.exit(res);
>>> }
>>> }
>>> ------------------------------
>>> Thank you for your kindly help !
>>>
>>
>>
>

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