public void process() {
        final Selection<Long> selection = getSelection();
        if (!selection.isMatchNothing()) {
            final ProcessChoicePresenter processChoicePresenter = processChoicePresenterProvider.get();
            final ProcessChoiceUiHandler processChoiceUiHandler = choice -> {
                if (choice.isReprocess()) {
                    doReprocess(choice);
                } else {
                    doProcess(choice);
                }
            };
            processChoicePresenter.show(selection, processChoiceUiHandler);
        } else {
            AlertEvent.fireError(
                    AbstractMetaListPresenter.this,
                    "You have not selected any items",
                    null);
        }
    }
@param onSetExpression Called after the expression has been successfully
                       validated and set on the criteria. Can be null.
stroom-core-client/src/main/java/stroom/data/client/presenter/AbstractMetaListPresenter.java