Thanks Nicholas, but it didn't worked. Can I do a remote debugging on hadoop examples? I really like to put a breakpoint in the Pi class.
Thanks, On Wed, Jan 26, 2011 at 6:46 PM, Tsz Wo (Nicholas), Sze <s29752-hadoopu...@yahoo.com> wrote: > Okay, I got it now. You were talking about your programs but not the > PiEstimator example came from Hadoop. Then, you have to set > "mapred.output.key.class" and "mapred.output.value.class" as Srihari > mentioned. Below are the APIs. > > //new API > final Job job = ... > job.setMapOutputKeyClass(BooleanWritable.class); > job.setMapOutputValueClass(LongWritable.class); > > //old API > final JobConf jobconf = ... > jobconf.setOutputKeyClass(BooleanWritable.class); > jobconf.setOutputValueClass(LongWritable.class); > > Nicholas > > ________________________________ > From: Srihari Anantha Padmanabhan <sriha...@yahoo-inc.com> > To: "mapreduce-user@hadoop.apache.org" <mapreduce-user@hadoop.apache.org> > Sent: Wed, January 26, 2011 10:36:09 AM > Subject: Re: PiEstimator error - Type mismatch in key from map > > I am using Hadoop 0.20.2. I just wrote my own map-reduce program based on > the map-reduce tutorial at > http://hadoop.apache.org/common/docs/r0.20.2/mapred_tutorial.html > > On Jan 26, 2011, at 10:27 AM, Pedro Costa wrote: > >> Hadoop 20.1 >> >> On Wed, Jan 26, 2011 at 6:26 PM, Tsz Wo (Nicholas), Sze >> <s29752-hadoopu...@yahoo.com> wrote: >>> Hi Srihari, >>> >>> Same questions to you: Which version of Hadoop are you using? And where >>> did >>> you get the examples? I guess you were able to reproduce it. I suspect >>> the >>> examples and the Hadoop are in different versions. >>> >>> Nicholas >>> >>> >>> ________________________________ >>> From: Srihari Anantha Padmanabhan <sriha...@yahoo-inc.com> >>> To: "mapreduce-user@hadoop.apache.org" <mapreduce-user@hadoop.apache.org> >>> Sent: Wed, January 26, 2011 10:15:08 AM >>> Subject: Re: PiEstimator error - Type mismatch in key from map >>> >>> I got a similar error before in one of my projects. I had to set the >>> values >>> for "mapred.output.key.class" and "mapred.output.value.class". >>> That resolved the issue for me. >>> Srihari >>> On Jan 26, 2011, at 10:09 AM, Pedro Costa wrote: >>> >>> Yes, I can reproduce it deterministically. But, I also did some >>> changes to the Hadoop MR code. Most definitely this is the reason. I'm >>> looking throughly through the code. >>> >>> I'll say something after I find the problem. >>> >>> I was just wondering if this error has happened to someone before. >>> Maybe I could get a hint and try to see what's my problem easily. >>> >>> Thanks, >>> >>> On Wed, Jan 26, 2011 at 6:02 PM, Tsz Wo (Nicholas), Sze >>> <s29752-hadoopu...@yahoo.com> wrote: >>> >>> Hi Pedro, >>> >>> This is interesting. Which version of Hadoop are you using? And where >>> did >>> >>> you get the example class files? Also, are you able to reproduce it >>> >>> deterministically? >>> >>> Nicholas >>> >>> ________________________________ >>> >>> From: Pedro Costa <psdc1...@gmail.com> >>> >>> To: mapreduce-user@hadoop.apache.org >>> >>> Sent: Wed, January 26, 2011 5:47:01 AM >>> >>> Subject: PiEstimator error - Type mismatch in key from map >>> >>> Hi, >>> >>> I run the PI example of hadoop, and I've got the following error: >>> >>> [code] >>> >>> java.io.IOException: Type mismatch in key from map: expected >>> >>> org.apache.hadoop.io.BooleanWritable, recieved >>> >>> org.apache.hadoop.io.LongWritable >>> >>> at >>> >>> >>> org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:885) >>> >>> at >>> >>> >>> org.apache.hadoop.mapred.MapTask$NewOutputCollector.write(MapTask.java:551) >>> >>> at >>> >>> >>> org.apache.hadoop.mapreduce.TaskInputOutputContext.write(TaskInputOutputContext.java:81) >>> >>> 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:637) >>> >>> at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343) >>> >>> at org.apache.hadoop.mapred.Child.main(Child.java:190) >>> >>> [/code] >>> >>> I've look at the map function of the class "PiEstimator.class" and it >>> seems >>> >>> ok. >>> >>> [code] >>> >>> public void map(LongWritable offset, >>> >>> LongWritable size, >>> >>> OutputCollector<BooleanWritable, LongWritable> out, >>> >>> Reporter reporter) throws IOException {} >>> >>> [/code] >>> >>> >>> What's wrong with this examples? >>> >>> Thanks, >>> >>> -- >>> >>> Pedro >>> >>> >>> >>> >>> -- >>> Pedro >>> >>> >> >> >> >> -- >> Pedro > > -- Pedro
