Java Text.write方法代碼示例

import org.apache.hadoop.io.Text; //導入方法依賴的package包/類
public WritableSortable(int j) throws IOException {
  seed = r.nextLong();
  r.setSeed(seed);
  Text t = new Text();
  StringBuilder sb = new StringBuilder();
  indices = new int[j];
  offsets = new int[j];
  check = new String[j];
  DataOutputBuffer dob = new DataOutputBuffer();
  for (int i = 0; i < j; ++i) {
    indices[i] = i;
    offsets[i] = dob.getLength();
    genRandom(t, r.nextInt(15) + 1, sb);
    t.write(dob);
    check[i] = t.toString();
  }
  eob = dob.getLength();
  bytes = dob.getData();
  comparator = WritableComparator.get(Text.class);
}
 

import org.apache.hadoop.io.Text; //導入方法依賴的package包/類
public void write(DataOutput dataOutput) throws IOException {
    Text text = new Text(wifiProb==null?"":wifiProb);
    text.write(dataOutput);

    LongWritable longWritable = new LongWritable();
    longWritable.set(hour);
    longWritable.write(dataOutput);
    longWritable.set(newCustomer);
    longWritable.write(dataOutput);
    longWritable.set(oldCustomer);
    longWritable.write(dataOutput);

}
 

import org.apache.hadoop.io.Text; //導入方法依賴的package包/類
public void write(DataOutput dataOutput) throws IOException {
    Text text = new Text(wifiProb==null?"":wifiProb);
    text.write(dataOutput);

    IntWritable intWritable = new IntWritable();

    intWritable.set(inNoOutWifi);
    intWritable.write(dataOutput);
    intWritable.set(inNoOutStore);
    intWritable.write(dataOutput);

    intWritable.set(outNoInWifi);
    intWritable.write(dataOutput);
    intWritable.set(outNoInStore);
    intWritable.write(dataOutput);

    intWritable.set(inAndOutWifi);
    intWritable.write(dataOutput);
    intWritable.set(inAndOutStore);
    intWritable.write(dataOutput);

    intWritable.set(stayInWifi);
    intWritable.write(dataOutput);
    intWritable.set(stayInStore);
    intWritable.write(dataOutput);

    DoubleWritable doubleWritable = new DoubleWritable();
    doubleWritable.set(jumpRate);
    doubleWritable.write(dataOutput);
    doubleWritable.set(deepVisit);
    doubleWritable.write(dataOutput);
    doubleWritable.set(inStoreRate);
    doubleWritable.write(dataOutput);
}
 

import org.apache.hadoop.io.Text; //導入方法依賴的package包/類
/**
 * Use the input splits to take samples of the input and generate sample
 * keys. By default reads 100,000 keys from 10 locations in the input, sorts
 * them and picks N-1 keys to generate N equally sized partitions.
 * @param job the job to sample
 * @param partFile where to write the output file to
 * @throws Throwable if something goes wrong
 */
public static void writePartitionFile(final JobContext job, 
    Path partFile) throws Throwable  {
  long t1 = System.currentTimeMillis();
  Configuration conf = job.getConfiguration();
  final TeraInputFormat inFormat = new TeraInputFormat();
  final TextSampler sampler = new TextSampler();
  int partitions = job.getNumReduceTasks();
  long sampleSize = conf.getLong(SAMPLE_SIZE, 100000);
  final List<InputSplit> splits = inFormat.getSplits(job);
  long t2 = System.currentTimeMillis();
  System.out.println("Computing input splits took " + (t2 - t1) + "ms");
  int samples = Math.min(conf.getInt(NUM_PARTITIONS, 10), splits.size());
  System.out.println("Sampling " + samples + " splits of " + splits.size());
  final long recordsPerSample = sampleSize / samples;
  final int sampleStep = splits.size() / samples;
  Thread[] samplerReader = new Thread[samples];
  SamplerThreadGroup threadGroup = new SamplerThreadGroup("Sampler Reader Thread Group");
  // take N samples from different parts of the input
  for(int i=0; i < samples; ++i) {
    final int idx = i;
    samplerReader[i] = 
      new Thread (threadGroup,"Sampler Reader " + idx) {
      {
        setDaemon(true);
      }
      public void run() {
        long records = 0;
        try {
          TaskAttemptContext context = new TaskAttemptContextImpl(
            job.getConfiguration(), new TaskAttemptID());
          RecordReader<Text, Text> reader = 
            inFormat.createRecordReader(splits.get(sampleStep * idx),
            context);
          reader.initialize(splits.get(sampleStep * idx), context);
          while (reader.nextKeyValue()) {
            sampler.addKey(new Text(reader.getCurrentKey()));
            records += 1;
            if (recordsPerSample <= records) {
              break;
            }
          }
        } catch (IOException ie){
          System.err.println("Got an exception while reading splits " +
              StringUtils.stringifyException(ie));
          throw new RuntimeException(ie);
        } catch (InterruptedException e) {
      	  
        }
      }
    };
    samplerReader[i].start();
  }
  FileSystem outFs = partFile.getFileSystem(conf);
  DataOutputStream writer = outFs.create(partFile, true, 64*1024, (short) 10, 
                                         outFs.getDefaultBlockSize(partFile));
  for (int i = 0; i < samples; i++) {
    try {
      samplerReader[i].join();
      if(threadGroup.getThrowable() != null){
        throw threadGroup.getThrowable();
      }
    } catch (InterruptedException e) {
    }
  }
  for(Text split : sampler.createPartitions(partitions)) {
    split.write(writer);
  }
  writer.close();
  long t3 = System.currentTimeMillis();
  System.out.println("Computing parititions took " + (t3 - t2) + "ms");
}