code: public void addIntExcExpression(final INodeReadTrx mTransaction, final boolean mIsIntersect) {
  
          assert getPipeStack().size() >= 2;
  
          final INodeReadTrx rtx = mTransaction;
  
          final AbsAxis mOperand2 = getPipeStack().pop().getExpr();
          final AbsAxis mOperand1 = getPipeStack().pop().getExpr();
  
          final AbsAxis axis =
              mIsIntersect ? new IntersectAxis(rtx, mOperand1, mOperand2) : new ExceptAxis(rtx, mOperand1,
                  mOperand2);
  
          if (getPipeStack().empty() || getExpression().getSize() != 0) {
              addExpressionSingle();
          }
          getExpression().add(axis);
      }
docs: Adds a intersect or a exception expression to the pipeline.
  
  @param mTransaction
  Transaction to operate with.
  @param mIsIntersect
  true, if expression is an intersection