Parkirat, This is a core Java concept which is mainly related to how Class inheritance works in Java and how the @Override annotation is used, and is not Hadoop specific. (It is also used while implementing interfaces since JDK 6.)
You can read about it here: http://tutorials.jenkov.com/java/annotations.html#override http://www.javapractices.com/topic/TopicAction.do?Id=223 Regards, Shahab On Sat, Aug 2, 2014 at 2:56 AM, Arun Allamsetty <[email protected]> wrote: > Hi, > > The @Override annotation worked because, without it the reduce method in > the superclass (Reducer) was being invoked, which basically writes the > input from the mapper class to the context object. Try to look up the > source code for the Reducer class online and you'll realize that. > > Hope that clears it up. > > Cheers, > Arun > > Sent from a mobile device. Please don't mind the typos. > Hi Shahab, > > Thanks for the response. > > I have added the @Override and somehow that worked. I have pasted the new > Reducer code below. > > Though, I did not understood the difference here, as if what I have done > differently. I might be a very silly reason though. > > ========================================================= > package com.test.hadoop; > > import java.io.IOException; > > import org.apache.hadoop.io.IntWritable; > import org.apache.hadoop.io.Text; > import org.apache.hadoop.mapreduce.Reducer; > > public class WordCountReducer extends Reducer<Text, IntWritable, Text, > IntWritable> { > > @Override > protected void reduce(Text key, Iterable<IntWritable> values, > Context > context) > throws IOException, InterruptedException { > > int sum = 0; > for (IntWritable val : values) { > sum += val.get(); > } > context.write(key, new IntWritable(sum)); > } > } > ========================================================= > > Regards, > Parkirat Bagga. > > > > -- > View this message in context: > > http://apache-hbase.679495.n3.nabble.com/Hbase-Mapreduce-API-Reduce-to-a-file-is-not-working-properly-tp4062141p4062240.html > Sent from the HBase User mailing list archive at Nabble.com. >
