private Optional findNodeToWatch()

in twill-zookeeper/src/main/java/org/apache/twill/internal/zookeeper/LeaderElection.java [324:353]

• 24 lines of code
• 8 McCabe index (conditional complexity)

  private Optional<String> findNodeToWatch(List<String> nodes) {
    // If this node path is not know, find it first.
    if (zkNodePath == null) {
      for (String node : nodes) {
        if (node.startsWith(guid)) {
          zkNodePath = zkFolderPath + "/" + node;
          break;
        }
      }
    }

    if (zkNodePath == null) {
      // Cannot find the node path, return null
      return null;
    }

    // Find the maximum node that the smaller than node created by this client.
    int currentId = Integer.parseInt(zkNodePath.substring(zkNodePath.indexOf(guid) + guid.length() + 1));
    String nodeToWatch = null;
    int maxOfMins = Integer.MIN_VALUE;
    for (String node : nodes) {
      int nodeId = Integer.parseInt(node.substring(guid.length() + 1));
      if (nodeId < currentId && nodeId > maxOfMins) {
        maxOfMins = nodeId;
        nodeToWatch = node;
      }
    }

    return nodeToWatch == null ? Optional.<String>absent() : Optional.of(nodeToWatch);
  }