public void actionPerformed(ActionEvent __event) {
        try {            
            Object OBJ = __event.getSource();
            Object read;
            File file;
            
            if (OBJ == _save || OBJ == _saveb) {
                file = selectFile(_objectfile);                
                
                if (_objectfile != null) {
                    writeObject(_objectfile);
                    _objectfile = file;
                }
                return;
            }                                        
            if (OBJ == _load || OBJ == _loadb) {
                file = selectFile(_objectfile);              
                if (file != null) {
                    read = readObject(_objectfile);
                    if (read == null) {
                        return;
                    }
                    _model = (IFCModel) read;
                    _model.register(this);
                    _objectfile = file;
                }
                return;
            }

        } catch (Exception EXC) {
            System.out.println(EXC.getMessage());
            EXC.printStackTrace();
        }
    }