/// <summary>Add all nodes from a dependent nodes list to excludedNodes.</summary> /// <returns>number of new excluded nodes</returns> private int AddDependentNodesToExcludedNodes(DatanodeDescriptor chosenNode, ICollection <Node> excludedNodes) { if (this.host2datanodeMap == null) { return(0); } int countOfExcludedNodes = 0; foreach (string hostname in chosenNode.GetDependentHostNames()) { DatanodeDescriptor node = this.host2datanodeMap.GetDataNodeByHostName(hostname); if (node != null) { if (excludedNodes.AddItem(node)) { countOfExcludedNodes++; } } else { Log.Warn("Not able to find datanode " + hostname + " which has dependency with datanode " + chosenNode.GetHostName()); } } return(countOfExcludedNodes); }