Submitting jobs to classic MR using new client API

[Kamesh]

Hi,

While debugging the YARN code, I come across following code snippet in 
YarnClientProtocolProvider.java

  @Override
  public ClientProtocol create(Configuration conf) throws IOException {
    if 
(MRConfig.YARN_FRAMEWORK_NAME.equals(conf.get(MRConfig.FRAMEWORK_NAME))) {
      return new YARNRunner(conf);
    }
    return null;
  }

  @Override
  public ClientProtocol create(InetSocketAddress addr, Configuration conf)
      throws IOException {
    return create(conf);
  }

By the second API, it is clear that we can connect to the classic MR 
using client API (using JobClient(jt address, conf) and hence submit the 
job using the same job client instance.).  However while initializing 
the cluster instance, the above functionality either creates a 
YarnRunner instance or returns null and hence client gets IOException. 
With this limitation we can't submit jobs to classic MR.

There is any reason behind providing this?

Please correct me if I understood wrongly.

--
Thanks&Regards,
Bh.V.S.Kamesh.