Re: NoSuchMethodException when running Map Task

[monobug <fu...@hotmail.com>]

Hey, I assume you've already figured it out, but for people like me,
stumbling through the same error, it appears to be caused by forgetting to
make your inner classes (the ones implementing the Mapper and Reducer
interfaces), static.

-stu


Dan Benjamin wrote:
> 
> Sorry, I should have mentioned I'm using hadoop version 0.18.1 and java
> 1.6.
> 
> 
> Dan Benjamin wrote:
>> 
>> I've got a simple hadoop job running on an EC2 cluster using the scripts
>> under src/contrib/ec2.  The map tasks all fail with the following error:
>> 
>> 08/10/07 15:11:00 INFO mapred.JobClient: Task Id :
>> attempt_200810071501_0001_m_000031_0, Status : FAILED
>> java.lang.RuntimeException: java.lang.NoSuchMethodException:
>> ManifestRetriever$Map.<init>()
>>         at
>> org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:80)
>>         at
>> org.apache.hadoop.mapred.MapRunner.configure(MapRunner.java:33)
>>         at
>> org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:58)
>>         at
>> org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:82)
>>         at org.apache.hadoop.mapred.MapTask.run(MapTask.java:223)
>>         at
>> org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2207)
>> Caused by: java.lang.NoSuchMethodException:
>> com.amazon.ec2.ebs.billing.ManifestRetriever$Map.<init>()
>>         at java.lang.Class.getConstructor0(Class.java:2706)
>>         at java.lang.Class.getDeclaredConstructor(Class.java:1985)
>>         at
>> org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:74)
>> 
>> I tried adding an explicit (public) no-arg constructor to the
>> ManifestRetriever.Map class but this gives me the same error.  Has anyone
>> encountered this problem before?
>> 
>> 
> 
> 

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