IOUtils.java 文件源码

/** Deserializes the object in the given datainput using
 * available Hadoop serializations.
 * @throws IOException */
public static<T> T deserialize(Configuration conf, DataInput in
    , T obj , Class<T> objClass) throws IOException {
  SerializationFactory serializationFactory = new SerializationFactory(getOrCreateConf(conf));
  Deserializer<T> deserializer = serializationFactory.getDeserializer(
      objClass);

  int length = WritableUtils.readVInt(in);
  byte[] arr = new byte[length];
  in.readFully(arr);
  List<ByteBuffer> list = new ArrayList<>();
  list.add(ByteBuffer.wrap(arr));

  try (ByteBufferInputStream is = new ByteBufferInputStream(list)) {
    deserializer.open(is);
    T newObj = deserializer.deserialize(obj);
    return newObj;

  }finally {
    if(deserializer != null)
      deserializer.close();
  }
}