public Map<String, AbstractConfiguration> findCacheElement(AbstractConfiguration config,
      CacheConfigurationManager manager) {
    Map<String, AbstractConfiguration> results = new HashMap<>();
    for (String group : persistenceService.getGroups()) {
      CacheConfig cacheConfig = persistenceService.getCacheConfig(group, true);
      AbstractConfiguration existing = manager.get(config, cacheConfig);
      if (existing != null) {
        results.put(group, existing);
      }
    }
    return results;
  }
this returns a map of CacheElement with this id, with the group as the key of the map
geode-core/src/main/java/org/apache/geode/management/internal/configuration/validators/MemberValidator.java