Yep, best to annotate your code with the @Override annotation so that you can detect troubles like these easily.
On Tue, Jul 12, 2011 at 5:07 PM, Devaraj K <[email protected]> wrote: > Hi Teng, > > > > As per the exception stack trace, it is not invoking the TaskMapper.map() > method and it is invoking the default Mapper.map() method. Can you recheck > the configurations and job code whether it is properly copied or not? > > > > Devaraj K > > ---------------------------------------------------------------------------- > --------------------------------------------------------- > This e-mail and its attachments contain confidential information from > HUAWEI, which > is intended only for the person or entity whose address is listed above. Any > use of the > information contained herein in any way (including, but not limited to, > total or partial > disclosure, reproduction, or dissemination) by persons other than the > intended > recipient(s) is prohibited. If you receive this e-mail in error, please > notify the sender by > phone or email immediately and delete it!ss > > > > _____ > > From: Teng, James [mailto:[email protected]] > Sent: Tuesday, July 12, 2011 12:16 PM > To: [email protected] > Subject: FW: type mismatch error > > > > hi, all. > > I am a new hadoop beginner, I try to construct a map and reduce task to run, > however encountered an exception while continue going further. > > Exception: > > java.io.IOException: Type mismatch in key from map: expected > org.apache.hadoop.io.Text, recieved org.apache.hadoop.io.LongWritable > > at > org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:845) > > at > org.apache.hadoop.mapred.MapTask$NewOutputCollector.write(MapTask.java:541) > > at > org.apache.hadoop.mapreduce.TaskInputOutputContext.write(TaskInputOutputCont > ext.java:80) > > at org.apache.hadoop.mapreduce.Mapper.map(Mapper.java:124) > > at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144) > > at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:621) > > at org.apache.hadoop.mapred.MapTask.run(MapTask.java:305) > > at > org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:177) > > Mapper: > > > > > > Any help is greatly appreciated! > > Thanks in advance. > > > > James, Teng (Teng Linxiao) > > eRL, CDC, eBay, Shanghai > > Extension: 86-21-28913530 > > MSN: <mailto:[email protected]> [email protected] > > Skype: James,Teng > > Email: [email protected] > > > > -- Harsh J
