demo.SsMapper.java Source code

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Here is the source code for demo.SsMapper.java

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/**
 * Copyright 2012 Jee Vang 
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at 
 * 
 *  http://www.apache.org/licenses/LICENSE-2.0 
 *  
 *  Unless required by applicable law or agreed to in writing, software 
 *  distributed under the License is distributed on an "AS IS" BASIS, 
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 *  See the License for the specific language governing permissions and 
 *  limitations under the License. 
 */
package demo;

import java.io.IOException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import java.util.Arrays;

/**
 * Secondary sort mapper.
 * @author Jee Vang
 *
 */
public class SsMapper extends Mapper<LongWritable, Text, StockKey, DoubleWritable> {

    private static final Log _log = LogFactory.getLog(SsMapper.class);

    @Override
    public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
        String[] tokens = value.toString().split(",");

        System.out.println("Array contents " + Arrays.toString(tokens));
        String symbol = tokens[0].trim();
        System.out.println("Symbol " + symbol);
        Long timestamp = Long.parseLong(tokens[1].trim());
        System.out.println("timestamp " + timestamp);

        Double v = Double.parseDouble(tokens[2].trim());

        System.out.println("double " + v);

        StockKey stockKey = new StockKey(symbol, timestamp);
        DoubleWritable stockValue = new DoubleWritable(v);

        context.write(stockKey, stockValue);
        _log.debug(stockKey.toString() + " => " + stockValue.toString());
    }
}