Java Code Examples for org.apache.hadoop.io.Writable#getClass()

@Override
public boolean writeNextObject(OneRow onerow) throws IOException {
    Writable value = (Writable) onerow.getData();
    Writable key = (Writable) onerow.getKey();

    // init writer on first approach here, based on onerow.getData type
    // TODO: verify data is serializable.
    if (writer == null) {
        Class<? extends Writable> valueClass = value.getClass();
        Class<? extends Writable> keyClass = (key == null) ? LongWritable.class
                : key.getClass();
        // create writer - do not allow overwriting existing file
        writer = SequenceFile.createWriter(fc, configuration, file, keyClass,
                valueClass, compressionType, codec,
                new SequenceFile.Metadata(), EnumSet.of(CreateFlag.CREATE));
    }

    try {
        writer.append((key == null) ? defaultKey : key, value);
    } catch (IOException e) {
        LOG.error("Failed to write data to file: {}", e.getMessage());
        return false;
    }

    return true;
}
 

/**
 * Read the next key in the file into <code>key</code>, skipping its value.  True if another
 * entry exists, and false at end of file.
 */
public synchronized boolean next(Writable key) throws IOException {
  if (key.getClass() != WALEntry.class) {
    throw new IOException("wrong key class: " + key.getClass().getName()
                          + " is not " + WALEntry.class);
  }

  outBuf.reset();

  keyLength = next(outBuf);
  if (keyLength < 0) {
    return false;
  }

  valBuffer.reset(outBuf.getData(), outBuf.getLength());

  key.readFields(valBuffer);
  valBuffer.mark(0);
  if (valBuffer.getPosition() != keyLength) {
    throw new IOException(key + " read " + valBuffer.getPosition()
                          + " bytes, should read " + keyLength);
  }


  return true;
}
 

private void writePrimitive(final Writable value) {
  if (value == null) {
    return;
  }
  if (value instanceof DoubleWritable) {
    recordConsumer.addDouble(((DoubleWritable) value).get());
  } else if (value instanceof BooleanWritable) {
    recordConsumer.addBoolean(((BooleanWritable) value).get());
  } else if (value instanceof FloatWritable) {
    recordConsumer.addFloat(((FloatWritable) value).get());
  } else if (value instanceof IntWritable) {
    recordConsumer.addInteger(((IntWritable) value).get());
  } else if (value instanceof LongWritable) {
    recordConsumer.addLong(((LongWritable) value).get());
  } else if (value instanceof ShortWritable) {
    recordConsumer.addInteger(((ShortWritable) value).get());
  } else if (value instanceof ByteWritable) {
    recordConsumer.addInteger(((ByteWritable) value).get());
  } else if (value instanceof BigDecimalWritable) {
    throw new UnsupportedOperationException("BigDecimal writing not implemented");
  } else if (value instanceof BinaryWritable) {
    recordConsumer.addBinary(((BinaryWritable) value).getBinary());
  } else {
    throw new IllegalArgumentException("Unknown value type: " + value + " " + value.getClass());
  }
}
 

private Writable updateColumnValue(RCFileColumn column, BytesRefWritable bytesRef) throws IOException {
  if(bytesRef.getLength() == 0) {
    // This is a null field.
    return NullWritable.get();
  }
  Writable newColumnValue = column.newWritable();
  // Small optimization to bypass DataInput read if the column writable is
  // BytesRefWritable
  if (newColumnValue.getClass() == BytesRefWritable.class) {
    newColumnValue = bytesRef;
  } else {
    byte[] currentRowBytes = Arrays.copyOfRange(bytesRef.getData(),
        bytesRef.getStart(), bytesRef.getStart() + bytesRef.getLength());
    DataInput dataInput = ByteStreams.newDataInput(currentRowBytes);
    newColumnValue.readFields(dataInput);
  }
  return newColumnValue;
}
 

/**
 * Read the next key/value pair in the file into <code>key</code> and <code>val</code>.  Returns
 * true if such a pair exists and false when at end of file
 */
public synchronized boolean next(Writable key, Writable val)
    throws IOException {
  if (val.getClass() != WALEntry.class) {
    throw new IOException("wrong value class: " + val + " is not " + WALEntry.class);
  }

  boolean more = next(key);

  if (more) {
    getCurrentValue(val);
  }

  return more;
}
 

/** Read the next key/value pair in the file into <code>key</code> and
 * <code>val</code>.  Returns true if such a pair exists and false when at
 * end of file */
public synchronized boolean next(Writable key, Writable val)
  throws IOException {
  if (val.getClass() != getValueClass())
    throw new IOException("wrong value class: "+val+" is not "+valClass);

  boolean more = next(key);
  
  if (more) {
    getCurrentValue(val);
  }

  return more;
}
 

/** Read the next key/value pair in the file into <code>key</code> and
 * <code>val</code>.  Returns true if such a pair exists and false when at
 * end of file */
public synchronized boolean next(Writable key, Writable val)
  throws IOException {
  if (val.getClass() != getValueClass())
    throw new IOException("wrong value class: "+val+" is not "+valClass);

  boolean more = next(key);
  
  if (more) {
    getCurrentValue(val);
  }

  return more;
}
 

@Override
public void write(Writable key, Writable value) throws IOException, InterruptedException {
  if (!init) {
    synchronized(props) {
      if (!init) {
        init();
      }
    }
  }
  
  //
  // Assume the value is a GTSWrapper
  //
  
  long count = 0L;

  TDeserializer deserializer = new TDeserializer(new TCompactProtocol.Factory());

  GTSWrapper gtsWrapper = new GTSWrapper();

  try {
    if (value instanceof BytesWritable) {
      deserializer.deserialize(gtsWrapper, ((BytesWritable) value).copyBytes());
    } else if (value instanceof Text) {
      deserializer.deserialize(gtsWrapper, OrderPreservingBase64.decode(((Text) value).copyBytes()));
    } else {
      throw new IOException("Invalid value class, expecting BytesWritable or Text, was " + value.getClass());
    }
  } catch (TException te) {
    throw new IOException(te);
  }

  Metadata metadataChunk;
  
  if (gtsWrapper.isSetMetadata()) {
    metadataChunk = new Metadata(gtsWrapper.getMetadata());
  } else {
    metadataChunk = new Metadata();
  }

  GTSDecoder decoder = GTSWrapperHelper.fromGTSWrapperToGTSDecoder(gtsWrapper);

  StringBuilder metasb = new StringBuilder();
  // We don't care about exposing labels since they are forced by the token
  GTSHelper.metadataToString(metasb, metadataChunk.getName(), metadataChunk.getLabels(), false);

  boolean first = true;

  while (decoder.next()) {
    if (null != this.limiter) {
      this.limiter.acquire(1);
    }

    if (!first) {
      this.pw.print("=");
      this.pw.println(GTSHelper.tickToString(null, decoder.getTimestamp(), decoder.getLocation(), decoder.getElevation(), decoder.getBinaryValue()));
    } else {
      pw.println(GTSHelper.tickToString(metasb, decoder.getTimestamp(), decoder.getLocation(), decoder.getElevation(), decoder.getBinaryValue()));
      first = false;
    }
    count++;
  }
}