Example usage for org.apache.hadoop.io Text Text

Introduction

In this page you can find the example usage for org.apache.hadoop.io Text Text.

Prototype

public Text(byte[] utf8)

Source Link

Document

Construct from a byte array.

Usage

From source file:Assignment3_P4_DateStock.DateStock_Reducer.java

public void reduce(Text key, Iterable<DateStock_CompositeValueWritable> values, Context context)
        throws IOException, InterruptedException {
    int minStockVol = 0;
    int maxStockVol = 0;
    Float maxStockPriceAdj = 0f;//from w  w w .  j a v a2s  .  c  om
    String minDate = "";
    String maxDate = "";
    int count = 0;

    for (DateStock_CompositeValueWritable value : values) {
        if (count < 1) {
            minStockVol = Integer.parseInt(value.getVolume());
            minDate = value.getDate();
            //System.out.println("Min date is " + minDate);
        }

        if (Integer.parseInt(value.getVolume()) < minStockVol) {
            minStockVol = Integer.parseInt(value.getVolume());
            minDate = value.getDate();
            //System.out.println("Min date is " + minDate);
        }

        if (Integer.parseInt(value.getVolume()) > maxStockVol) {
            maxStockVol = Integer.parseInt(value.getVolume());
            maxDate = value.getDate();
            //System.out.println("Max date is " + maxDate);
        }

        if (Float.parseFloat(value.getMaxStockPrice()) > maxStockPriceAdj) {
            maxStockPriceAdj = Float.parseFloat(value.getMaxStockPrice());
        }

        count++;
    }

    String op = minDate + "\t" + maxDate + "\t" + String.valueOf(maxStockPriceAdj);
    Text out = new Text(op);
    context.write(key, out);

}

From source file:Assignment4_P2_StockAverageWithCombiner.StockAverage_Mapper.java

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

    if (!stockInfo[1].trim().equals("stock_symbol")) {
        String[] dateParts = stockInfo[2].split("-");
        Text year = new Text(dateParts[0]);

        stockPriceAdjCompositeObj.setCount(1);
        stockPriceAdjCompositeObj.setAverage(stockInfo[8]);

        context.write(year, stockPriceAdjCompositeObj);
    }//w  w w . j a va2s  .  c om
}

From source file:Assignment4_P3_InMemoryStdDeviation.MovieRatingStdDev_Reducer.java

public void reduce(IntWritable key, Iterable<FloatWritable> values, Context context)
        throws IOException, InterruptedException {
    int running_sum = 0;
    int running_count = 0;
    float median = 0;

    for (FloatWritable val : values) {
        list.add((float) val.get());
        running_sum += val.get();
        running_count++;/*from   w  w  w  .  j  a va2  s .c o  m*/
    }

    Collections.sort(list);

    // calculating median
    if (list.size() % 2 == 0) {
        median = (list.get((running_count / 2) - 1) + list.get((running_count / 2))) / 2;
    } else {
        median = list.get((running_count / 2));
    }

    // calculating mean
    float mean = running_sum / running_count;

    // calculating standard deviation
    float sumSquare = 0;
    float stdDev = 0;
    for (Float oneValue : list) {
        sumSquare += (oneValue - mean) * (oneValue - mean);
    }

    // finally, std dev
    stdDev = (float) Math.sqrt(sumSquare / (running_count - 1));

    //.append(median)
    String outcome = new StringBuilder().append("\t").append(stdDev).append("\t").append(running_sum)
            .append("\t").append(running_count).toString();
    result = new Text(outcome);
    context.write(key, result);
}

From source file:Assignment4_P4_MemoryConscious.MovieRatingMemConscious_Reducer.java

public void reduce(IntWritable key, Iterable<SortedMapWritable> values, Context context)
        throws IOException, InterruptedException {
    int running_count = 0;
    long running_sum = 0;
    float median = 0;
    list = new TreeMap<>();

    // loop through all ratings in received hashmap for this movieID
    for (SortedMapWritable val : values) {

        // iterate through every entry consisting of movieRating, countOfRating for ex (4.5, 10) i.e 10 people rated it 4.5
        for (Map.Entry<WritableComparable, Writable> entry : val.entrySet()) {

            // extract movieRating for ex : 4.5
            FloatWritable number = (FloatWritable) entry.getKey();
            float movieRating = number.get();

            //extract countOfRating for ex : 10
            LongWritable counter = (LongWritable) entry.getValue();
            long count = counter.get();

            // calculate running sum by multiplying movieRating and countRating i.e (4.5 * 10 = 45)
            running_sum += (movieRating * count);

            // increment running count for getting average later i.e 10
            running_count += count;//from  w w  w .ja v  a  2s.  c o m

            // make <count> entries for <movieRating> in new hashmap i.e  (4.5, 10)
            if (list.containsKey(movieRating)) {
                list.put(movieRating, list.get(movieRating) + count);
            } else {
                list.put(movieRating, count);
            }

        }
    }

    System.out.println("Running count for movieID " + key + " is :- " + running_count);
    System.out.println("Rating List size for movieID " + key + " is :- " + list.size());

    // calculating mean
    float mean = running_sum / running_count;
    System.out.println("Mean for movieID " + key + " is :- " + mean);

    // calculating standard deviation
    float sumSquare = 0;
    float stdDev = 0;
    for (Map.Entry<Float, Long> entry : list.entrySet()) {
        sumSquare += (entry.getKey() - mean) * (entry.getKey() - mean) * (entry.getValue());
    }

    // finally, std dev
    stdDev = (float) Math.sqrt(sumSquare / (running_count - 1));
    System.out.println("Standard deviation for movieID " + key + " is :- " + stdDev);

    //.append(median)
    String outcome = new StringBuilder().append("\t").append(stdDev).append("\t").append(running_sum)
            .append("\t").append(running_count).toString();
    result = new Text(outcome);
    context.write(key, result);
}

From source file:Assignment5_P2_DistinctIPAddress.DistinctIPAddress_Mapper.java

public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
    String[] ipInfo = value.toString().split("-");
    ipaddr = new Text(ipInfo[0].trim());
    context.write(ipaddr, NullWritable.get());
}

From source file:Assignment5_P6_StructureToHierarchyPattern.Structure_Hierarchy_Movie_Mapper.java

public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
    String[] movieInfo = value.toString().split(",");
    String movieId = movieInfo[0];

    //append 'T' for title identification
    String movieTitle = "T" + movieInfo[1];

    // movieID, movieTitle
    context.write(new Text(movieId), new Text(movieTitle));
}

From source file:Assignment5_P6_StructureToHierarchyPattern.Structure_Hierarchy_Reducer.java

@Override
protected void setup(Context context) throws IOException, InterruptedException {
    context.write(null, new Text("<MovieAndGenre>"));
}

From source file:Assignment5_P6_StructureToHierarchyPattern.Structure_Hierarchy_Reducer.java

public void reduce(Text key, Iterable<Text> values, Context context) throws IOException, InterruptedException {
    sb.append("<Movie>");

    for (Text value : values) {
        if (value.toString().charAt(0) == 'T' && count < 1) {
            String title = value.toString().substring(1, value.toString().length()).trim();
            // put it in a tag
            sb.append("<Title>").append(title).append("</Title>");
            // in count so next time it doesnt come in
            count++;/*from  www .  j  av  a2s .c o m*/
        } else {
            String tag = value.toString().substring(1, value.toString().length()).trim();

            // call genre fellow
            constructPropertyXml(tag);
        }
    }

    sb.append("</Movie>");
    context.write(null, new Text(sb.toString()));
}

From source file:Assignment5_P6_StructureToHierarchyPattern.Structure_Hierarchy_Reducer.java

@Override
protected void cleanup(Context context) throws IOException, InterruptedException {
    context.write(null, new Text("</MovieAndGenre>"));
}

From source file:Assignment5_P6_StructureToHierarchyPattern.Structure_Hierarchy_Tag_Mapper.java

public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
    String[] movieInfo = value.toString().split(",");
    String movieId = movieInfo[1];

    //append 'A' for tag identification
    String movieTag = "A" + movieInfo[2];

    // movieID, movieTag
    context.write(new Text(movieId), new Text(movieTag));
}