package com.manning.hip.ch2;
import com.manning.hip.ch3.avro.gen.Stock;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.hbase.mapreduce.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapreduce.*;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import java.io.IOException;
import static com.manning.hip.ch2.HBaseWriteAvroStock.*;
public class HBaseSourceMapReduce extends
TableMapper<Text, DoubleWritable> {
private HBaseScanAvroStock.AvroStockReader stockReader;
private Text outputKey = new Text();
private DoubleWritable outputValue = new DoubleWritable();
@Override
protected void setup(
Context context)
throws IOException, InterruptedException {
stockReader = new HBaseScanAvroStock.AvroStockReader();
}
@Override
public void map(ImmutableBytesWritable row, Result columns,
Context context)
throws IOException, InterruptedException {
for (KeyValue kv : columns.list()) {
byte[] value = kv.getValue();
Stock stock = stockReader.decode(value);
outputKey.set(stock.symbol.toString());
outputValue.set(stock.close);
context.write(outputKey, outputValue);
}
}
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
Scan scan = new Scan();
scan.addColumn(STOCK_DETAILS_COLUMN_FAMILY_AS_BYTES,
STOCK_COLUMN_QUALIFIER_AS_BYTES);
Job job = new Job(conf);
job.setJarByClass(HBaseSourceMapReduce.class);
TableMapReduceUtil.initTableMapperJob(
STOCKS_TABLE_NAME,
scan,
HBaseSourceMapReduce.class,
ImmutableBytesWritable.class,
Put.class,
job);
job.setNumReduceTasks(0);
job.setMapOutputKeyClass(Text.class);
job.setMapOutputValueClass(DoubleWritable.class);
Path outputPath = new Path(args[0]);
FileOutputFormat.setOutputPath(job, outputPath);
outputPath.getFileSystem(conf).delete(outputPath, true);
job.waitForCompletion(true);
}
}