Programming CORBA with Orbacus on Linux

Publishing references of server objects

Converting a reference into a string

The method

CORBA::String_ptr CORBA::ORB::object_to_string(CORBA::ORB::Object_ptr)

A typical usage is the following:

try {
  X_impl* impl = new X_impl();
  X_var servant = impl->_this();

  CORBA::String_var strRef = orb->object_to_string(servant);

  <do something with the reference, e.g. store in a file>
  const char* refFile = "X.ref";
  ofstream out(refFile);
  out << strRef << endl;
  out.close();
} catch (const CORBA::SystemException& e){
  // something was wrong with CORBA
} catch (...){
  // something else was wrong
}

The stringified references can be transferred from server to the client by storing them in ordinary files, sending via email or using other methods. The simplest method is to store them in files. An example for publishing a server reference via a file-based IOR is given here.

Publishing references with CORBALOC

Instead of writing the reference to a server object into a file or publish the stringified reference in another way, you can use the boot manager to publish the reference under a freely choosen name via CORBALOC. You add a binding from this object ID to the reference to the boot manager:

  OB::BootManager_var bootManager = <get boot manager from somewhere>
  X_var xv = <get server reference from somewhere>
  PortableServer::ObjectId_var oid = PortableServer::string_to_ObjectId("/Serverobjectname");
  bootManager->add_binding(oid, xv);

In a real-world example, you use the CORBALOC binding as follows:

try {
  // create implementation object
  X_impl* xImpl = new X_impl();
  PortableServer::ObjectId_var oid = PortableServer::string_to_ObjectId("/Serverobjectname");
  PortableServer::ServantBase_var servant = xImpl;
  poa->activate_object_with_id(oid, servant);

  // resolve boot manager and register server
  CORBA::Object_var bootObj = orb->resolve_initial_references("BootManager");
  if (CORBA::is_nil(bootObj)){
    // handle error
  }
  OB::BootManager_var bootManager = OB::BootManager::_narrow(bootObj);
  if (CORBA::is_nil(bootManager)){
    // handle error
  }

  // publish reference via corbaloc naming service
  X_var xv = xImpl->_this();
  bootManager->add_binding(oid, xv);
} catch (const CORBA::SystemException& e){
  // handle error
}

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