private void addListSelectionHandler() {
        registerHandler(listPresenter.getSelectionModel().addSelectionHandler(event -> {
            final DataRetentionRule rule = listPresenter.getSelectionModel().getSelected();
            if (rule != null) {
                expressionPresenter.read(rule.getExpression());
                if (event.getSelectionType().isDoubleSelect() && !isDefaultRule(rule)) {
                    edit(rule);
                }
            } else {
                expressionPresenter.read(null);
            }
            updateButtons();
        }));
    }
@return The rules created by the users, ignoring the default retain all rule
stroom-core-client/src/main/java/stroom/receive/rules/client/presenter/DataRetentionPolicyPresenter.java