private void processVer3()

in src/main/java/org/apache/datasketches/theta/UnionImpl.java [401:461]
51 lines of code
12 McCabe index (conditional complexity)

  private void processVer3(final Memory skMem) {
    final int preLongs = extractPreLongs(skMem);

    if (preLongs == 1) {
      if (otherCheckForSingleItem(skMem)) {
        final long hash = skMem.getLong(8);
        gadget_.hashUpdate(hash);
        return;
      }
      return; //empty
    }
    ThetaUtil.checkSeedHashes(expectedSeedHash_, (short)extractSeedHash(skMem));
    final int curCountIn;
    final long thetaLongIn;

    if (preLongs == 2) { //exact mode
      curCountIn = extractCurCount(skMem);
      if (curCountIn == 0) { return; } //should be > 0, but if it is 0 return empty anyway.
      thetaLongIn = Long.MAX_VALUE;
    }

    else { //prelongs == 3
      //curCount may be 0 (e.g., from intersection); but sketch cannot be empty.
      curCountIn = extractCurCount(skMem);
      thetaLongIn = extractThetaLong(skMem);
    }

    unionThetaLong_ = min(min(unionThetaLong_, thetaLongIn), gadget_.getThetaLong()); //theta rule
    unionEmpty_ = false;
    final int flags = extractFlags(skMem);
    final boolean ordered = (flags & ORDERED_FLAG_MASK) != 0;
    if (ordered) { //must be compact

      for (int i = 0; i < curCountIn; i++ ) {
        final int offsetBytes = preLongs + i << 3;
        final long hashIn = skMem.getLong(offsetBytes);
        if (hashIn >= unionThetaLong_) { break; } // "early stop"
        gadget_.hashUpdate(hashIn); //backdoor update, hash function is bypassed
      }
    }

    else { //not-ordered, could be compact or hash-table form
      final boolean compact = (flags & COMPACT_FLAG_MASK) != 0;
      final int size = compact ? curCountIn : 1 << extractLgArrLongs(skMem);

      for (int i = 0; i < size; i++ ) {
        final int offsetBytes = preLongs + i << 3;
        final long hashIn = skMem.getLong(offsetBytes);
        if (hashIn <= 0L || hashIn >= unionThetaLong_) { continue; }
        gadget_.hashUpdate(hashIn); //backdoor update, hash function is bypassed
      }
    }

    unionThetaLong_ = min(unionThetaLong_, gadget_.getThetaLong()); //sync thetaLongs

    if (gadget_.hasMemory()) {
      final WritableMemory wmem = (WritableMemory)gadget_.getMemory();
      PreambleUtil.insertUnionThetaLong(wmem, unionThetaLong_);
      PreambleUtil.clearEmpty(wmem);
    }
  }