Question

Can somebody give one good example link for mapreduce with Hbase? My requirement is run mapreduce on hdfs file and store reducer output to hbase table. Mapper input will be hdfs file and output will be Text,IntWritable key value pairs. Reducers output will be Put object ie add reducer Iterable IntWritable values and store in hbase table.

Answer 1

Here is the code which will solve your problem

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Driver

HBaseConfiguration conf =  HBaseConfiguration.create();
Job job = new Job(conf,"JOB_NAME");
    job.setJarByClass(yourclass.class);
    job.setMapperClass(yourMapper.class);
    job.setMapOutputKeyClass(Text.class);
    job.setMapOutputValueClass(Intwritable.class);
    FileInputFormat.setInputPaths(job, new Path(inputPath));
    TableMapReduceUtil.initTableReducerJob(TABLE,
            yourReducer.class, job);
    job.setReducerClass(yourReducer.class);
            job.waitForCompletion(true);

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Mapper&Reducer

class yourMapper extends Mapper<LongWritable, Text, Text,IntWritable> {
//@overide map()
 }

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class yourReducer
        extends
        TableReducer<Text, IntWritable, 
        ImmutableBytesWritable>
{
//@override rdeuce()
}

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