private void addItemsFromInspector(CompositeItem item, Inspector inspector){
        if (inspector.type() == ARRAY){
            inspector.traverse((ArrayTraverser) (index, new_value) -> {
                item.addItem(walkJson(new_value));
            });

        } else if (inspector.type() == OBJECT){
            if (inspector.field("children").valid()) {
                inspector.field("children").traverse((ArrayTraverser) (index, new_value) -> {
                    item.addItem(walkJson(new_value));
                });
            }

        }
    }
Translates a list of grouping requests on JSON form to a list in the grouping language form
container-search/src/main/java/com/yahoo/search/query/SelectParser.java