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Date: Mon, 19 Jul 2010 17:38:24 +0200
From: Khaled BEN BAHRI <Khaled.Ben_bahri@it-sudparis.eu>
To: mapreduce-user@hadoop.apache.org
Subject: error when executing mapreduce program
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Hello :)

I developped my first mapreduce program with eclipse.

when i want to execute it i have this error i tried to solve it but i failed :



Jul 19, 2010 5:06:37 PM org.apache.hadoop.mapred.JobClient monitorAndPrintJob
INFO: Task Id : attempt_201007191410_0002_m_000001_1, Status : FAILED
java.lang.NullPointerException
	at  
org.apache.hadoop.io.serializer.SerializationFactory.getSerializer(SerializationFactory.java:73)
	at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.<init>(MapTask.java:797)
	at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:350)
	at org.apache.hadoop.mapred.MapTask.run(MapTask.java:307)
	at org.apache.hadoop.mapred.Child.main(Child.java:170)




thanks for any help

best regards