2. Exceptions

2.1 C++ exceptions: class SALOME_Exception

definition

The class SALOME_Exception provides a generic method to send a message, with optional source file name and line number. This class is intended to serve as a base class for all kinds of exceptions SALOME code. All the exceptions derived from SALOME_Exception could be handled in a single catch, in which the message associated to the exception is displayed, or sent to a log file.

The class SALOME_Exception inherits its behavior from the STL class exception.

usage

The header SALOME/src/utils/utils_SALOME_Exception.hxx must be included in the C++ source, when raised or trapped:

#include "utils_SALOME_Exception.hxx"

The SALOME_Exception constructor is:

SALOME_Exception( const char *text,
                  const char *fileName=0, 
                  const unsigned int lineNumber=0 );

The exception is raised like this:

throw SALOME_Exception("my pertinent message");

or like this:

throw SALOME_Exception(LOCALIZED("my pertinent message"));

where LOCALIZED is a macro provided with utils_SALOME_Exception.hxx which gives file name and line number.

The exception is handled like this:

try
  {
    ...
  }
catch (const SALOME_Exception &ex)
  {
    cerr << ex.what() <<endl;
  }

The what() method overrides the one defined in the STL exception class.

2.2 CORBA exceptions

definition

The idl SALOME_Exception provides a generic CORBA exception for SALOME, with an attribute that gives an exception type,a message, plus optional source file name and line number.

This idl is intended to serve for all user CORBA exceptions raised in SALOME code, as IDL specification does not support exception inheritance. So, all the user CORBA exceptions from SALOME could be handled in a single catch.

The exception types defined in idl are:

COMM

CORBA communication problem,

BAD_PARAM

Bad User parameters,

INTERNAL_ERROR

application level problem (often irrecoverable).

CORBA system and user exceptions already defined in the packages used within SALOME, such as OmniORB exceptions, must be handled separately.

usage

CORBA servant, C++

The CORBA Server header for SALOME_Exception and a macro to throw the exception are provided with the header SALOME/src/Utils/Utils_CorbaException.hxx:

#include "Utils_CorbaException.hxx"

The exception is raised with a macro which appends file name and line number.

if (myStudyName.size() == 0)
   THROW_SALOME_CORBA_EXCEPTION("No Study Name given", \
                                SALOME::BAD_PARAM);

CORBA Client, GUI Qt C++

The CORBA Client header for SALOME_Exception and a Qt function header that displays a message box are provided in SALOME/src/SALOMEGUI/SALOMEGUI_QtCatchCorbaException.hxx:

#include "SALOMEGUI_QtCatchCorbaException.hxx"

A typical exchange with a CORBA Servant will be:

try
  {
    ... // one ore more CORBA calls
  }
catch (const SALOME::SALOME_Exception & S_ex)
  {
    QtCatchCorbaException(S_ex);
  }

CORBA Client, C++, without GUI

Nothing specific has been provided to the developer yet. See the idl or the Qt function SALOMEGUI_QtCatchCorbaException.hxx to see how to get the information given by the exception object.