code: public static Map<String, StoreDefinition> getUserStoreDefMapOnNode(AdminClient adminClient,
                                                                          Integer nodeId) {
          List<StoreDefinition> storeDefinitionList = adminClient.metadataMgmtOps.getRemoteStoreDefList(nodeId)
                                                                                 .getValue();
          Map<String, StoreDefinition> storeDefinitionMap = Maps.newHashMap();
          for(StoreDefinition storeDefinition: storeDefinitionList) {
              storeDefinitionMap.put(storeDefinition.getName(), storeDefinition);
          }
          return storeDefinitionMap;
      }
docs: Utility function that fetches user defined store definitions
  
  @param adminClient An instance of AdminClient points to given cluster
  @param nodeId Node id to fetch store definitions from
  @return The map container that maps store names to store definitions