/** {@inheritDoc} */
  @Override
  public void writeExternal(ObjectOutput out) throws IOException {
    U.writeString(out, jobName);
    U.writeString(out, user);

    out.writeBoolean(hasCombiner);
    out.writeInt(numReduces);

    U.writeStringMap(out, props);
  }
 /**
  * @param out Output stream.
  * @param err Error cause.
  */
 private void sendErrorResponse(ObjectOutput out, Exception err) {
   try {
     out.writeObject(new IpcSharedMemoryInitResponse(err));
   } catch (IOException e) {
     U.error(log, "Failed to send error response to client.", e);
   }
 }
 /** {@inheritDoc} */
 @Override
 public void writeExternal(ObjectOutput out) throws IOException {
   out.writeInt(max);
 }