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@G-Sudarshan
Created February 11, 2022 10:57
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import java.io.IOException;
import java.io.InvalidObjectException;
import java.util.Iterator;
import java.util.StringTokenizer;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
public class WordCountdemo {
public static class MyMap extends MapReduceBase implements Mapper<LongWritable,Text,Text,IntWritable>
{
private Text mykey = new Text();
public void map(LongWritable key, Text value , OutputCollector<Text,IntWritable> output, Reporter reporter) throws IOException
{
String Line = value.toString();
StringTokenizer tokenizer = new StringTokenizer(Line);
while(tokenizer.hasMoreTokens())
{
mykey.set(tokenizer.nextToken());
output.collect(mykey, new IntWritable(1));
}
}
}
public static class MyReduce extends MapReduceBase implements Reducer<Text,IntWritable,Text,IntWritable>
{
public void reduce(Text key , Iterator<IntWritable> values , OutputCollector<Text , IntWritable> output, Reporter reporter) throws IOException
{
int sum=0;
while(values.hasNext())
{
sum += values.next().get();
}
output.collect(key, new IntWritable(sum));
}
}
public static void main(String args[]) throws Exception
{
JobConf conf = new JobConf(WordCountdemo.class);
conf.setJobName("MyFirstProgram");
conf.setMapperClass(MyMap.class);
//conf.setCombiner(Combiner.class);
conf.setReducerClass(MyReduce.class);
conf.setOutputKeyClass(Text.class);
conf.setOutputValueClass(IntWritable.class);
conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);
FileInputFormat.setInputPaths(conf,new Path(args[0]));
FileOutputFormat.setOutputPath(conf, new Path(args[1]));
JobClient.runJob(conf);
}
}
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