code: void addInputSplitToLog(final ExecutionVertex vertex, final int sequenceNumber, final InputSplit inputSplit) {
  
  		final List<InputSplit> inputSplitLog = this.splitMap.get(vertex.getID());
  		if (inputSplitLog == null) {
  			LOG.error("Cannot find input split log for vertex " + vertex + " (" + vertex.getID() + ")");
  			return;
  		}
  
  		synchronized (inputSplitLog) {
  			if (inputSplitLog.size() != sequenceNumber) {
  				LOG.error("Expected input split with sequence number " + inputSplitLog.size() + " for vertex " + vertex
  					+ " (" + vertex.getID() + ") but received " + sequenceNumber + ", skipping...");
  				return;
  			}
  
  			inputSplitLog.add(inputSplit);
  		}
  	}
docs: Adds the given input split to the vertex's log and stores it under the specified sequence number.
  
  @param vertex
  the vertex for which the input split shall be stored
  @param sequenceNumber
  the sequence number identifying the log entry under which the input split shall be stored
  @param inputSplit
  the input split to be stored