public Tuple exec()

in src/main/java/org/apache/datasketches/pig/hll/AlgebraicIntermediate.java [66:102]
30 lines of code
10 McCabe index (conditional complexity)

  public Tuple exec(final Tuple inputTuple) throws IOException {
    if (this.isFirstCall_) {
      Logger.getLogger(getClass()).info("Algebraic was used");
      this.isFirstCall_ = false;
    }
    if (inputTuple == null || inputTuple.size() == 0) {
      return getEmptySketchTuple();
    }
    final DataBag outerBag = (DataBag) inputTuple.get(0);
    if (outerBag == null) {
      return getEmptySketchTuple();
    }
    final Union union = new Union(this.lgK_);
    for (final Tuple dataTuple: outerBag) {
      final Object f0 = dataTuple.get(0); // inputTuple.bag0.dataTupleN.f0
      if (f0 == null) { continue; }
      if (f0 instanceof DataBag) {
        final DataBag innerBag = (DataBag) f0; // inputTuple.bag0.dataTupleN.f0:bag
        if (innerBag.size() == 0) { continue; }
        // If field 0 of a dataTuple is a Bag, all innerTuples of this inner bag
        // will be passed into the union.
        // It is due to system bagged outputs from multiple mapper Initial functions.
        // The Intermediate stage was bypassed.
        updateUnion(innerBag, union);
      } else if (f0 instanceof DataByteArray) { // inputTuple.bag0.dataTupleN.f0:DBA
        // If field 0 of a dataTuple is a DataByteArray, we assume it is a sketch
        // due to system bagged outputs from multiple mapper Intermediate functions.
        // Each dataTuple.DBA:sketch will merged into the union.
        final DataByteArray dba = (DataByteArray) f0;
        union.update(HllSketch.wrap(Memory.wrap(dba.get())));
      } else { // we should never get here
        throw new IllegalArgumentException("dataTuple.Field0 is not a DataBag or DataByteArray: "
            + f0.getClass().getName());
      }
    }
    return tupleFactory_.newTuple(new DataByteArray(union.getResult(this.tgtHllType_).toCompactByteArray()));
  }