@Override public BigDecimal evaluate(QueryEval eval) { Object firstValue = multiplyExprs[0].evaluate(eval); BigDecimal result = new BigDecimal(firstValue.toString()); for (int i = 1; i < multiplyExprs.length; i++) { Object nextValue = multiplyExprs[i].evaluate(eval); BigDecimal operand = new BigDecimal(nextValue.toString()); result = operators.get(i - 1) ? result.add(operand) : result.subtract(operand); } return result; }