I did a map only job for sorting a txt file by editing wordcount program.
I only need the key .
How to set value to null.
*public class SortingCsv {*
* public static class Map extends Mapper<LongWritable, Text, Text,
IntWritable> {*
* private final static IntWritable one = new IntWritable(1);*
* private Text word = new Text();*
* public void map(LongWritable key, Text value, Context context) throws
IOException, InterruptedException {*
* System.out.println("in mapper");*
* String line = value.toString();*
* StringTokenizer tokenizer = new StringTokenizer(line);*
* while (tokenizer.hasMoreTokens()) {*
* word.set(tokenizer.nextToken());*
* context.write(word, one);*
* System.out.println("sort: "+word);*
* }*
* }*
* } *
*public static void main(String[] args) throws Exception {
System.out.println("in main"); Configuration conf = new Configuration();
Job job = new Job(conf, "wordcount");
job.setJarByClass(SortingCsv.class); //Path intermediateInfo = new
Path("out"); job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
job.setMapperClass(Map.class); FileSystem fs = FileSystem.get(conf); /*
Delete the files if any in the output path */ if (fs.exists(new
Path(args[1]))) fs.delete(new Path(args[1]), true);
job.setInputFormatClass(TextInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
FileInputFormat.addInputPath(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
job.waitForCompletion(true); } }*
On Wed, Jan 15, 2014 at 2:50 PM, unmesha sreeveni <[email protected]>wrote:
> How to sort a csv file
> I know , between map and reduce shuffle and sort is taking place.
> But how do i sort each column in a csv file?
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
> Junior Developer
>
> http://www.unmeshasreeveni.blogspot.in/
>
>
>
--
*Thanks & Regards*
Unmesha Sreeveni U.B
Junior Developer
http://www.unmeshasreeveni.blogspot.in/
