@Override
 public void reduce(
     IntWritable key,
     Iterator<Text> values,
     OutputCollector<IntWritable, Text> output,
     Reporter reporter)
     throws IOException {
   StringBuilder sb = new StringBuilder();
   while (values.hasNext()) {
     sb.append("," + values.next());
   }
   v.set(sb.toString().replaceFirst(",", "")); // 去掉第一个逗号
   output.collect(key, v);
   // 键为itemID,值为其打过分的所有用户的偏好
   System.out.println(key.toString() + "	" + v.toString());
 }
Пример #2
0
 @Override
 protected void map(Centroid key, IntWritable value, Context context)
     throws IOException, InterruptedException {
   context.write(new Text(key.toString()), new Text(value.toString()));
 }
 @Override
 public String toString() {
   return "<key: " + key.toString() + ", partition: " + partition.toString() + ">";
 }
    @Override
    public void reduce(
        IntWritable key,
        Iterator<ClusterWritable> values,
        OutputCollector<IntWritable, Text> output,
        Reporter reporter)
        throws IOException {

      float sumSimilarity = 0.0f;
      int numMovies = 0;
      float avgSimilarity = 0.0f;
      float similarity = 0.0f;
      int s = 0;
      int count;
      float diff = 0.0f;
      float minDiff = 1.0f;
      int candidate = 0;
      String data = new String("");
      String shortline = new String("");
      ArrayList<String> arrl = new ArrayList<String>();
      ArrayList<Float> simArrl = new ArrayList<Float>();
      String oneElm = new String();
      int indexShort, index2;
      Text val = new Text();

      while (values.hasNext()) {
        ClusterWritable cr = (ClusterWritable) values.next();
        similarity = cr.similarity;
        simArrl.addAll(cr.similarities);
        for (int i = 0; i < cr.movies.size(); i++) {
          oneElm = cr.movies.get(i);
          indexShort =
              oneElm.indexOf(
                  ",",
                  1000); // to avoid memory error caused by long arrays; it will results less
                         // accurate
          if (indexShort == -1) {
            shortline = new String(oneElm);
          } else {
            shortline = new String(oneElm.substring(0, indexShort));
          }
          arrl.add(shortline);
          output.collect(key, new Text(oneElm));
        }
        numMovies += cr.movies.size();
        sumSimilarity += similarity;
      }
      if (numMovies > 0) {
        avgSimilarity = sumSimilarity / (float) numMovies;
      }
      diff = 0.0f;
      minDiff = 1.0f;
      for (s = 0; s < numMovies; s++) {
        diff = (float) Math.abs(avgSimilarity - simArrl.get(s));
        if (diff < minDiff) {
          minDiff = diff;
          candidate = s;
        }
      }
      data = arrl.get(candidate);
      index2 = data.indexOf(":");
      String movieStr = data.substring(0, index2);
      String reviews = data.substring(index2 + 1);
      StringTokenizer token = new StringTokenizer(reviews, ",");
      count = 0;
      while (token.hasMoreTokens()) {
        token.nextToken();
        count++;
      }
      System.out.println(
          "The key = "
              + key.toString()
              + " has members = "
              + numMovies
              + " simil = "
              + simArrl.get(candidate));
      val = new Text(simArrl.get(candidate) + " " + movieStr + " " + count + " " + reviews);
      output.collect(key, val);
      reporter.incrCounter(Counter.VALUES, 1);
    }
Пример #5
0
 @Override
 public String toString() {
   return first.toString() + ":" + second.toString();
 }