public Map<String, MetaData> getMetaDataMap() {
        return META_DATA_MAP;
    }
-> Collections 'spring/A', 'spring/B'
        Set<String> paths = MAPPING.get(metaPath);
        if (Objects.isNull(paths)) {
            MAPPING.putIfAbsent(metaPath, new ConcurrentSkipListSet<>());
            paths = MAPPING.get(metaPath);
        }
        paths.add(path);
    }
    
    /**
get metaDataMap.

@return metaDataMap
shenyu-plugin/shenyu-plugin-base/src/main/java/org/apache/shenyu/plugin/base/cache/MetaDataCache.java