CORBA AMI call not producing callback?

Question

I'm modifying the stock quoter example from the wustl CORBA release. The assignment is to implement a reply handler for the StockFactory class that handles calls to get_stock()

Here's my FactoryHandler implementation:

FactoryHandler_i.h:

#ifndef TAO_TUTORIALS_QUOTER_AMI_CLIENT_FACTORYHANDLER_I_H
#define TAO_TUTORIALS_QUOTER_AMI_CLIENT_FACTORYHANDLER_I_H

#include "QuoterS.h"

class Stock_Factory_Handler_i : public POA_Quoter::AMI_Stock_FactoryHandler
{
public:
Stock_Factory_Handler_i (int *response_count, ::Quoter::Stock_var& result);

    void get_stock (::Quoter::Stock_ptr ami_return_val);
    void get_stock_excep (::Messaging::ExceptionHolder * excep_holder);

private:
    int *response_count_;
    ::Quoter::Stock_var& result_;
};

#endif /* TAO_TUTORIALS_QUOTER_AMI_CLIENT_HANDLER_I_H */

FactoryHandler_i.cpp:

#include "FactoryHandler_i.h"
#include "ace/streams.h"

Stock_Factory_Handler_i::
    Stock_Factory_Handler_i (int *response_count, ::Quoter::Stock_var& result)
    : response_count_ (response_count), result_ (result)
{
}

void
Stock_Factory_Handler_i::get_stock (::Quoter::Stock_ptr ami_return_val)
{
  cout << "storing result" << endl;
  result_ = ami_return_val;
  (*this->response_count_)++;
}

void
Stock_Factory_Handler_i::get_stock_excep (::Messaging::ExceptionHolder * excep_holder)
{
  // We ignore the exception, but this counts as a response, otherwise
  // the application would not finish.
  cerr << "Exception raised while getting stock"
       << endl;
  (*this->response_count_)++;
}

And the client.cpp, from just before the part where changes have been made:

// ...
// Create and activate the handler...
int response_count = 0;
Single_Query_Stock_Handler_i handler_i (&response_count);
Quoter::AMI_Single_Query_StockHandler_var handler =
  handler_i._this ();

// Create and activate the factory handler...
Quoter::Stock_var result;
Stock_Factory_Handler_i factory_handler_i (&response_count, result);
Quoter::AMI_Stock_FactoryHandler_var factory_handler =
  factory_handler_i._this();

// Send all the requests, careful with error handling
int request_count = 0;
for (int i = 2; i != argc+1; ++i) {
  try {
    // Get the stock object
      cout << "looking up stock symbol " << argv[i] << endl;
    factory->sendc_get_stock (factory_handler.in (), argv[i]);
     sleep(3);  // wait for a response
      cout << "converting result" << endl;
    Quoter::Single_Query_Stock_var stock =
      Quoter::Single_Query_Stock::_narrow (result.in ());
      cout << "checking result" << endl;
      CORBA::Any any;
      any <<= stock;
      CORBA::TypeCode_var tc = any.type();
      cout << tc->kind() << endl;
    if (CORBA::is_nil (stock.in ())) {
      cerr << "Cannot get single query interface for <"
           << argv[i] << ">" << endl;
      continue;
    }
      cout << "reading result" << endl;
    stock->sendc_get_price_and_names (handler.in ());
    request_count++;
  }
  catch (Quoter::Invalid_Stock_Symbol &) {
    cerr << "Invalid stock symbol <"
         << argv[i] << ">" << endl;
  }
}

while (response_count < 2 * request_count   // multiply by 2 because both handlers increment response_count
       && orb->work_pending ()) {
  orb->perform_work ();
}
// ...

When running the client, the output is:

looking up stock symbol MSFT
converting result
checking result
14
Cannot get single query interface for <MSFT> 

(The 14 is the typecode for Stock, that's only for debugging)

Notably missing from the above is the "storing result" message that's supposed to be printed in the FactoryHandler's get_stock() callback method. I'm at a loss as to why, since the sendc_get_stock() method doesn't produce any (immediate) errors and is basically just a copy of the StockHandler's code, and from there it's the responsibility of the AMI/ORB interface to make the callback. But the original example (with a StockHandler only) works fine.

What am I doing wrong (and how do I fix it)?

EDIT: another bit of information: on the server side, StockFactory's get_stock() method does get called.

Answer 1

Sorry, I've no aswer for you. But a hint, ask your question at TOA's maling list at http://www.cs.wustl.edu/~schmidt/ACE-mail.html

HTH