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From manish dunani <manishd...@gmail.com>
Subject Re: [Error]Finding average using hbase hadoop
Date Fri, 16 Aug 2013 13:09:42 GMT
Hello jean,
I did the same as u told me..
But,still face the same error.Didn't get any idea,what would be wrong??
If u find then please do more elaboration on it..


On Fri, Aug 16, 2013 at 5:02 PM, Jean-Marc Spaggiari <
jean-marc@spaggiari.org> wrote:

> Hi Manish,
>
> First, instead of "stocks".getBytes() you need to use
> Bytes.toBytes("stocks"). Same for the other strings.
> Second, on your map task, you creates 2 bytes arrays for those string at
> each iteration. You don't want that on a production environment. You should
> move that outside of the map method and make them final static.
>
> JM
>
> 2013/8/16 manish dunani <manishd207@gmail.com>
>
> > hello,
> >
> > I am using apache hadoop 1.1.2 and hbase 0.94.9 on pseudo distibuted
> mode.
> >
> > I am trying to find Average open stocks values.
> >
> > *sample dataset in hbase::**(table name:nyse4)*
> >
> >
> >  2010-02-04           column=stocks:open, timestamp=1376567559424,
> > value=2.5
> >  2010-02-04           column=stocks:symbol, timestamp=1376567559424,
> > value=QXM
> >  2010-02-05           column=stocks:open, timestamp=1376567559429,
> > value=2.42
> >  2010-02-05           column=stocks:symbol, timestamp=1376567559429,
> > value=QXM
> >  2010-02-08           column=stocks:open, timestamp=1376567559431,
> > value=2.33
> >  2010-02-08           column=stocks:symbol, timestamp=1376567559431,
> > value=QXM
> >
> > *code:*(please ignores the lines that are commenting)
> >
> >
> > > package com.maddy;
> > >
> > > import java.io.IOException;
> > >
> > > import org.apache.hadoop.conf.Configuration;
> > > import org.apache.hadoop.fs.Path;
> > > import org.apache.hadoop.hbase.HBaseConfiguration;
> > > import org.apache.hadoop.hbase.client.Put;
> > > import org.apache.hadoop.hbase.client.Result;
> > > import org.apache.hadoop.hbase.client.Scan;
> > > import org.apache.hadoop.hbase.filter.FirstKeyOnlyFilter;
> > > import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
> > > import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
> > > import org.apache.hadoop.hbase.mapreduce.TableMapper;
> > > import org.apache.hadoop.hbase.mapreduce.TableReducer;
> > > import org.apache.hadoop.hbase.util.Bytes;
> > > //import org.apache.hadoop.io.DoubleWritable;
> > > import org.apache.hadoop.io.FloatWritable;
> > > import org.apache.hadoop.mapreduce.Job;
> > > import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
> > >
> > >
> > > public class openaveragestock
> > > {
> > >     public static class map extends
> > > TableMapper<ImmutableBytesWritable,FloatWritable>
> > >     {
> > >         @Override
> > >
> > >         public void map(ImmutableBytesWritable row,Result value,Context
> > > context) throws IOException
> > >         {
> > >
> > >             byte[]
> > > val=(value.getValue("stocks".getBytes(),"open".getBytes()));
> > >             //byte[]
> > > val1=(value.getValue("stocks".getBytes(),"symbol".getBytes()));
> > >
> > >
> > >             ImmutableBytesWritable stock_symbol=new
> > > ImmutableBytesWritable("symbol".getBytes());
> > >
> > >
> > >             try
> > >             {
> > >                 context.write(stock_symbol,new
> > > FloatWritable(Bytes.toFloat(val)));
> > >             }
> > >             catch(InterruptedException e)
> > >
> > >             {
> > >                  throw new IOException(e);
> > >             }
> > >
> > >
> > >         }
> > >
> > >
> > >     }
> > >
> > >
> > >     public static class reduce extends
> > >
> TableReducer<ImmutableBytesWritable,FloatWritable,ImmutableBytesWritable>
> > >     {
> > >
> > >         @Override
> > >         public void reduce(ImmutableBytesWritable
> > > key,Iterable<FloatWritable>values,Context context) throws IOException,
> > > InterruptedException
> > >         {
> > >             float sum=0;
> > >             int count=0;
> > >           //  float average=0;
> > >             for(FloatWritable val:values)
> > >             {
> > >                 sum+=val.get();
> > >                 count++;
> > >             }
> > >             //average=(sum/count);
> > >             Put put=new Put(key.get());
> > >
> > >
> >
> put.add(Bytes.toBytes("stocks_output"),Bytes.toBytes("average"),Bytes.toBytes(sum/count));
> > >             System.out.println("For\t"+count+"\t average
> > is:"+(sum/count));
> > >             context.write(key,put);
> > >
> > >         }
> > >
> > >     }
> > >
> > >     public static void main(String args[]) throws IOException,
> > > ClassNotFoundException, InterruptedException
> > >     {
> > >         Configuration config=HBaseConfiguration.create();
> > >         config.addResource("/home/manish/workspace/hbase
> > > project/bin/hbase-site.xml");
> > >         Job job=new Job(config,"openstockaverage1");
> > >
> > >
> > >         Scan scan=new Scan();
> > >         scan.addFamily("stocks".getBytes());
> > >         scan.setFilter(new FirstKeyOnlyFilter());
> > >
> > >         TableMapReduceUtil.initTableMapperJob("nyse4",
> > >                 scan,
> > >                 map.class,
> > >                 ImmutableBytesWritable.class,
> > >                 FloatWritable.class,
> > >                 job);
> > >
> > >         TableMapReduceUtil.initTableReducerJob("nyse5",
> > >                 reduce.class,
> > >                 job);
> > >         //job.setReducerClass(reduce.class);
> > >
> > >         FileOutputFormat.setOutputPath(job, new Path(
> > >
> > "hdfs://localhost:54310/user/manish/edurekahbasehadoop1"));
> > >         job.waitForCompletion(true);
> > >     }
> > >
> > > }
> > >
> > >
> > >
> > > *===>Got stuck into error:*
> > >
> > >
> > > 13/08/16 03:21:45 INFO mapred.JobClient: Running job: job_local_0001
> > > 13/08/16 03:21:46 INFO mapred.JobClient:  map 0% reduce 0%
> > > 13/08/16 03:21:46 INFO mapreduce.TableOutputFormat: Created table
> > instance
> > > for nyse5
> > > 13/08/16 03:21:46 INFO util.ProcessTree: setsid exited with exit code 0
> > > 13/08/16 03:21:47 INFO mapred.Task:  Using ResourceCalculatorPlugin :
> > > org.apache.hadoop.util.LinuxResourceCalculatorPlugin@50b77c
> > > 13/08/16 03:21:47 INFO mapred.MapTask: io.sort.mb = 100
> > > 13/08/16 03:21:53 INFO mapred.MapTask: data buffer = 79691776/99614720
> > > 13/08/16 03:21:53 INFO mapred.MapTask: record buffer = 262144/327680
> > > 13/08/16 03:21:54 WARN mapred.LocalJobRunner: job_local_0001
> > > java.lang.IllegalArgumentException: offset (0) + length (4) exceed the
> > > capacity of the array: 3
> > >     at
> > >
> >
> org.apache.hadoop.hbase.util.Bytes.explainWrongLengthOrOffset(Bytes.java:543)
> > >     at org.apache.hadoop.hbase.util.Bytes.toInt(Bytes.java:690)
> > >     at org.apache.hadoop.hbase.util.Bytes.toFloat(Bytes.java:584)
> > >     at org.apache.hadoop.hbase.util.Bytes.toFloat(Bytes.java:574)
> > >     at com.maddy.openaveragestock$map.map(openaveragestock.java:41)
> > >     at com.maddy.openaveragestock$map.map(openaveragestock.java:1)
> > >     at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
> > >     at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)
> > >     at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
> > >     at
> > >
> org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:214)
> > >
> > >
> > I cannot find where is it fail??
> > Can you please tell me??
> > where i was wrong..?
> >
> >
> > Your help will be appreciated.
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > --
> > Regards
> >
> > *Manish Dunani*
> > *Contact No* : +91 9408329137
> > *skype id* : manish.dunani*
> > *
> >
>



-- 
Regards

*Manish Dunani*
*Contact No* : +91 9408329137
*skype id* : manish.dunani*
*

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