Example Documentation

A separate log category should be used for different functional parts of the program. In this example, "MAIN" (implicitly), "A", and "B" are used.

Different message levels should be used to note importance to the different messages, so that very important messages will be noticed, but lower priority messages can be filtered or ignored.

// $Id: example-logging.cc,v 1.1 2005/07/29 02:55:16 mschatz Exp $
// Demonstrates how Foundation logging can be used

#include "Foundation.hh"

// Some functional section of the program.
// Note how both insertion style and string messages are logged.

// The logManager is explicitly passed in so that this section
// can ask for its own LogCategory
void workA(Logger * logManager, int i)
{
  LogCategory log = logManager->getCategory("A");

  log.setMessageLevel(i * 10);
  log << "Message from A, i=" << i << endl;
  log.debug("Message is at MESSAGE_LEVEL_DEBUG_HIGH");
}




// Some different functional section of the program
void workB(Logger * logManager, int i)
{
  LogCategory log = logManager->getCategory("B");

  log.log("This message is at the default message level");

  // Use the message level stack for making quick changes to the message level
  log.pushMessageLevel(MESSAGE_LEVEL_DEBUG_ERROR);

  // Messages are only written to the log when a '\n' newline character is
  // written
  log << "ERROR message from B, i=";
  log << i << endl;
  
  // Go back to the old message level
  log.popMessageLevel();
}





int main(int argc, char ** argv)
{
  string helptext = "Foundation logging example";
  string version = "Foundation example-logging 1.0";
  string dependencies = "Foundation";

  try
  {
    // Instantiate Foundation
    Foundation *app = new Foundation (version, 
                                                helptext, 
                                                dependencies,
                                                argc, 
                                                argv);
    
    // Parse the command line for options (--filterlevel, --logfile, ...)
    app->handleStandardOptions();

    // Main Program
    // The logManager is created as soon as handleStandardOptions is called
    Logger * logManager = app->getLogger();
    LogCategory main = app->log();

    for (int i = 1; i < 8; i++)
    {
      main << "In Main Program i=" << i << endl;

      workA(logManager, i);
      workB(logManager, i);
    }

    // Delete Foundation
    delete app;
  }
  catch (ExitProgramNormally e)
  {
    // non fatal error (help, version, or dependencies were requested)
  }
  catch (Exception e)
  {
    // fatal error
    
    cerr << e << endl;
    exit (100);
  }

  return 0;
}