...
grid.addListener(Events.RowDoubleClick, new Listener<BaseEvent>() {

                @Override
                public void handleEvent(BaseEvent baseEvent) {
                    GridEvent gridEvent = (GridEvent) baseEvent;
                    String data = gridEvent.getModel().get("propertyName");
                }
            });
...

...
grid.getSelectionModel().addListener(Events.SelectionChange, new Listener<SelectionChangedEvent<ModelData>>() {
        
        @Override
        public void handleEvent(SelectionChangedEvent<ModelData> gridEvent) {
           List<ModelData> selection = gridEvent.getSelection());
        }
    });

...

...
gridEvent.getGrid().getView().getCell(gridEvent.getRowIndex(),columnNumber);

...

...
int getCellCount(int row);
...

...
List<ModelData> selection = gridEvent.getSelection());
...