code: public static Logging init(String ds_name, int trace_level, Database db) {
          if (_instance == null) {
              _instance = new Logging(ds_name, trace_level, db);
          }
          return _instance;
      }
docs: Create and get the singleton object reference.
  <p>
  This method returns a reference to the object of the Logging class.
  If the class singleton object has not been created, it will be
  instanciated
  
  @param ds_name The device server executable name
  @param db      The database object
  @return The Logging object reference