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From yypvsxf19870706 <yypvsxf19870...@gmail.com>
Subject Re: Multiple ways to write Hadoop program driver - Which one to choose?
Date Wed, 24 Apr 2013 13:50:11 GMT
Hi sheikhar

   The deprecated job constructor is actually deprecated according to the job source code
. 
   There is another constructor witch is not deprecated ,you can find in the hint raised by
eclipse .

  




发自我的 iPhone

在 2013-4-24,13:53,Chandrashekhar Kotekar <shekhar.kotekar@gmail.com> 写道:

> Hi,
> 
> 
> I have observed that there are multiple ways to write driver method of Hadoop program.
> 
> Following method is given in Hadoop Tutorial by Yahoo
> 
> 
>  public void run(String inputPath, String outputPath) throws Exception {
>     JobConf conf = new JobConf(WordCount.class);
>     conf.setJobName("wordcount");
> 
>     // the keys are words (strings)
>     conf.setOutputKeyClass(Text.class);
>     // the values are counts (ints)
>     conf.setOutputValueClass(IntWritable.class);
> 
>     conf.setMapperClass(MapClass.class);
>     conf.setReducerClass(Reduce.class);
> 
>     FileInputFormat.addInputPath(conf, new Path(inputPath));
>     FileOutputFormat.setOutputPath(conf, new Path(outputPath));
> 
>     JobClient.runJob(conf);
>   }
> and this method is given in Hadoop The Definitive Guide 2012 book by Oreilly.
> 
> 
> public static void main(String[] args) throws Exception {
>   if (args.length != 2) {
>     System.err.println("Usage: MaxTemperature <input path> <output path>");
>     System.exit(-1);
>   }
>   Job job = new Job();
>   job.setJarByClass(MaxTemperature.class);
>   job.setJobName("Max temperature");
>   FileInputFormat.addInputPath(job, new Path(args[0]));
>   FileOutputFormat.setOutputPath(job, new Path(args[1]));
>   job.setMapperClass(MaxTemperatureMapper.class);
>   job.setReducerClass(MaxTemperatureReducer.class);
>   job.setOutputKeyClass(Text.class);
>   job.setOutputValueClass(IntWritable.class);
>   System.exit(job.waitForCompletion(true) ? 0 : 1);
> }
> While trying program given in Oreilly book I found that constructors of Job class are
deprecated. As Oreilly book is based on Hadoop 2 (yarn) I was surprised to see that they have
used deprecated class.
> 
> I would like to know which method everyone uses?
> 
> 
> 
> 
> 
> 
> 
> 
> Regards,
> Chandrash3khar K0tekar
> Mobile - 8884631122
> 

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