public Tuple next()

in tajo-core/tajo-core-backend/src/main/java/org/apache/tajo/engine/planner/physical/BNLJoinExec.java [93:197]
96 lines of code
24 McCabe index (conditional complexity)

  public Tuple next() throws IOException {

    if (leftTupleSlots.isEmpty()) {
      for (int k = 0; k < TUPLE_SLOT_SIZE; k++) {
        Tuple t = leftChild.next();
        if (t == null) {
          leftEnd = true;
          break;
        }
        leftTupleSlots.add(t);
      }
      leftIterator = leftTupleSlots.iterator();
      leftTuple = leftIterator.next();
    }

    if (rightTupleSlots.isEmpty()) {
      for (int k = 0; k < TUPLE_SLOT_SIZE; k++) {
        Tuple t = rightChild.next();
        if (t == null) {
          rightEnd = true;
          break;
        }
        rightTupleSlots.add(t);
      }
      rightIterator = rightTupleSlots.iterator();
    }

    if((rightNext = rightChild.next()) == null){
      rightEnd = true;
    }

    while (true) {
      if (!rightIterator.hasNext()) { // if leftIterator ended
        if (leftIterator.hasNext()) { // if rightTupleslot remains
          leftTuple = leftIterator.next();
          rightIterator = rightTupleSlots.iterator();
        } else {
          if (rightEnd) {
            rightChild.rescan();
            rightEnd = false;
            
            if (leftEnd) {
              return null;
            }
            leftTupleSlots.clear();
            for (int k = 0; k < TUPLE_SLOT_SIZE; k++) {
              Tuple t = leftChild.next();
              if (t == null) {
                leftEnd = true;
                break;
              }
              leftTupleSlots.add(t);
            }
            if (leftTupleSlots.isEmpty()) {
              return null;
            }
            leftIterator = leftTupleSlots.iterator();
            leftTuple = leftIterator.next();
            
          } else {
            leftIterator = leftTupleSlots.iterator();
            leftTuple = leftIterator.next();
          }
          
          rightTupleSlots.clear();
          if (rightNext != null) {
            rightTupleSlots.add(rightNext);
            for (int k = 1; k < TUPLE_SLOT_SIZE; k++) { // fill right
              Tuple t = rightChild.next();
              if (t == null) {
                rightEnd = true;
                break;
              }
              rightTupleSlots.add(t);
            }
          } else {
            for (int k = 0; k < TUPLE_SLOT_SIZE; k++) { // fill right
              Tuple t = rightChild.next();
              if (t == null) {
                rightEnd = true;
                break;
              }
              rightTupleSlots.add(t);
            }
          }
          
          if ((rightNext = rightChild.next()) == null) {
            rightEnd = true;
          }
          rightIterator = rightTupleSlots.iterator();
        }
      }

      frameTuple.set(leftTuple, rightIterator.next());
      if (hasJoinQual) {
        if (joinQual.eval(inSchema, frameTuple).isTrue()) {
          projector.eval(frameTuple, outputTuple);
          return outputTuple;
        }
      } else {
        projector.eval(frameTuple, outputTuple);
        return outputTuple;
      }
    }
  }