docs: public static Map<String, List<String>> getPartitionsForTopics(ZkClient zkClient, Collection<String> topics) {
          Map<String, List<String>> ret = new HashMap<String, List<String>>();
          for (String topic : topics) {
              List<String> partList = new ArrayList<String>();
              List<String> brokers = getChildrenParentMayNotExist(zkClient, BrokerTopicsPath + "/" + topic);
              if (brokers != null) {
                  for (String broker : brokers) {
                      final String parts = readData(zkClient, BrokerTopicsPath + "/" + topic + "/" + broker);
                      int nParts = Integer.parseInt(parts);
                      for (int i = 0; i < nParts; i++) {
                          partList.add(broker + "-" + i);
                      }
                  }
              }
              Collections.sort(partList);
              ret.put(topic, partList);
          }
          return ret;
      }