code: boolean isInputConsumable(int inputNumber) {
  		return Arrays.stream(inputEdges[inputNumber]).map(ExecutionEdge::getSource).anyMatch(
  				IntermediateResultPartition::isConsumable);
  	}
docs: Get whether an input of the vertex is consumable.
  An input is consumable when when any partition in it is consumable.
  
  Note that a BLOCKING result partition is only consumable when all partitions in the result are FINISHED.
  
  @return whether the input is consumable