public static Map<String, String> transStringMap(final Map<String, Object> map) {
        return Optional.ofNullable(map)
                .map(m -> m.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey, e -> Objects.toString(e.getValue(), null))))
                .orElse(null);
    }
Transform to string map.

@param map source map
@return string map
shenyu-common/src/main/java/org/apache/shenyu/common/utils/MapUtils.java