hadoop MR从hbase中读取数据写入到hbase中

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hadoop MR从hbase中读取数据写入到hbase中的配置

public class WordCount {    private static final Logger LOGGER= LoggerFactory.getLogger(WordCount.class);    static class HbaseMapper extends TableMapper<ImmutableBytesWritable,Put>{        @Override        protected void map(ImmutableBytesWritable row, Result result, Context context) throws IOException, InterruptedException {            byte[] b = row.get();            String keys = Bytes.toString(b);            byte[] value=result.getValue(Bytes.toBytes(Constants.COLUMN_FAMILY),Bytes.toBytes("f1"));            LOGGER.info("------keys---::::"+keys);            LOGGER.info("------values---::::"+Bytes.toString(value));            context.write(row, resultToPut(row,result));        }        private static Put resultToPut(ImmutableBytesWritable key, Result result) throws IOException {            Put put = new Put(key.get());            for (KeyValue kv : result.raw()) {                put.add(kv);            }            return put;        }    }    public static void main(String[] args) throws Exception    {        Configuration config = HBaseConfiguration.create();        Job job = Job.getInstance(config,"mytest");        job.setJarByClass(WordCount.class);     // class that contains mapper        Scan scan = new Scan();        //rpc请求的记录数        scan.setCaching(500);        // 1 is the default in Scan, which will be bad for MapReduce jobs        scan.setCacheBlocks(false);  // don't set to true for MR jobs        TableMapReduceUtil.initTableMapperJob(                Constants.TableName.TEST,        // input HBase table name                scan,             // Scan instance to control CF and attribute selection                HbaseMapper.class,   // mapper                null,             // mapper output key                null,             // mapper output value                job);        TableMapReduceUtil.initTableReducerJob(                Constants.TableName.RECEIVE,      // output table                null,             // reducer class                job);        job.setNumReduceTasks(0);        System.exit(job.waitForCompletion(true) ? 0 : 1);    }}

hadoop MR从hbase中读取数据写入到hbase中的配置

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