public String toConfig() {
        final ObjectNode node = JsonUtils.createObjectNode();
        JsonUtils.setText(node, CONFIG_KEY_NAME, StringUtils.isBlank(getName()) ? null : getName());
        JsonUtils.setBoolean(node, CONFIG_KEY_ADV_MODE, isOpenInAdvancedMode());
        JsonUtils.setBoolean(node, CONFIG_KEY_INCLUDE_INCLUSIVE, isIncludeInconclusive());
        JsonUtils.set(node, CONFIG_KEY_TREE, JsonConfigurationUtils.toJsonConfig(getTree()));
        return JsonUtils.nodeToString(node);
    }
Extracts quickfilter settings from this filter. For each quickfilter, an entry is returned
For each quickfilter, it is stored whether corresponding caches shall be shown (true) or not (false)
main/src/main/java/cgeo/geocaching/filters/core/GeocacheFilter.java