SLIDE 7 10/30/17 7
WordCount Mapper in Java
Oct 30, 2017 Sprenkle - CSCI325 13
public public static static class class TokenizerMapper TokenizerMapper
extends extends Mapper<Object, Text, Text, Mapper<Object, Text, Text, IntWritable IntWritable> { > { private private final final static static IntWritable IntWritable one
= new new IntWritable IntWritable(1); (1); private private Text Text word word = = new new Text(); Text(); public public void void map(Object map(Object key key, Text , Text value value, Context , Context context context)
throws throws IOException IOException, , InterruptedException InterruptedException { { StringTokenizer itr = new new StringTokenizer StringTokenizer(value value.toString .toString()); ()); while while ( (itr itr.hasMoreTokens .hasMoreTokens()) { ()) { word.set(itr.nextToken()); context.write(word, one
); } } }
WordCount Reducer in Java
Oct 30, 2017 Sprenkle - CSCI325 14
public public static static class class IntSumReducer IntSumReducer extends extends Reducer<Text, Reducer<Text, IntWritable IntWritable, Text, , Text, IntWritable IntWritable> { > { private private IntWritable IntWritable result result = = new new IntWritable IntWritable(); (); public public void void reduce(Text reduce(Text key key, , Iterable Iterable<IntWritable IntWritable> > values values, Context , Context context context) throws throws IOException IOException, , InterruptedException InterruptedException { { int int sum sum = 0; = 0; for for ( (IntWritable IntWritable val val : : values values) { ) { sum += val.get(); } result.set(sum); context.write(key, result); } }
