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POMapReduce Job not showing my print statements on the terminal
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  1. POMapReduce Job not showing my print statements on the terminal
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    copied!<p>I am currently trying to figure out when you run a MapReduce job what happens by making some system.out.println() at certain places on the code but know of those print statement gets to print on my terminal when the job runs. Can someone help me out figure out what exactly am i doing wrong here.</p> <pre><code>import java.io.IOException; import java.util.StringTokenizer; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.InputSplit; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.OutputCommitter; import org.apache.hadoop.mapreduce.RecordReader; import org.apache.hadoop.mapreduce.RecordWriter; import org.apache.hadoop.mapreduce.Reducer; import org.apache.hadoop.mapreduce.StatusReporter; import org.apache.hadoop.mapreduce.TaskAttemptID; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; public class WordCountJob { public static int iterations; public static class TokenizerMapper extends Mapper&lt;Object, Text, Text, IntWritable&gt;{ private final static IntWritable one = new IntWritable(1); private Text word = new Text(); @Override public void map(Object key, Text value, Context context ) throws IOException, InterruptedException { System.out.println("blalblbfbbfbbbgghghghghghgh"); StringTokenizer itr = new StringTokenizer(value.toString()); while (itr.hasMoreTokens()) { word.set(itr.nextToken()); String myWord = itr.nextToken(); int n = 0; while(n&lt; 5){ myWord = myWord+ "Test my appending words"; n++; } System.out.println("Print my word: "+myWord); word.set(myWord); context.write(word, one); } } } public static class IntSumReducer extends Reducer&lt;Text,IntWritable,Text,IntWritable&gt; { private IntWritable result = new IntWritable(); public void reduce(Text key, Iterable&lt;IntWritable&gt; values, Context context ) throws IOException, InterruptedException { int sum = 0; for (IntWritable val : values) { sum += val.get(); } result.set(sum); context.write(key, result); } } public static void main(String[] args) throws Exception { Configuration conf = new Configuration(); TaskAttemptID taskid = new TaskAttemptID(); TokenizerMapper my = new TokenizerMapper(); if (args.length != 3) { System.err.println("Usage: WordCountJob &lt;in&gt; &lt;out&gt; &lt;iterations&gt;"); System.exit(2); } iterations = new Integer(args[2]); Path inPath = new Path(args[0]); Path outPath = null; for (int i = 0; i&lt;iterations; ++i){ System.out.println("Iteration number: "+i); outPath = new Path(args[1]+i); Job job = new Job(conf, "WordCountJob"); job.setJarByClass(WordCountJob.class); job.setMapperClass(TokenizerMapper.class); job.setCombinerClass(IntSumReducer.class); job.setReducerClass(IntSumReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(IntWritable.class); FileInputFormat.addInputPath(job, inPath); FileOutputFormat.setOutputPath(job, outPath); job.waitForCompletion(true); inPath = outPath; } } } </code></pre>
 

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