"代码微变，质变！优雅编程的炼金术"

同城研发加文雄2023年08月17日约 7 分钟

一、需求开发修改代码

一次需求开发时碰到如下所示方法代码：

private OrderShoudSettlementAmount getOrderShoudSettlementAmount(OrderDTO orderMain, List<SettlementDetail> details) {    OrderShoudSettlementAmount settlementAmount = new OrderShoudSettlementAmount();    // 应结金额=33021-33002-32003+32001-31001    // 货款佣金=33005+33002+32003+31001    long feeMoney33021 = 0;    long feeMoney33002 = 0;    long feeMoney32003 = 0;    long feeMoney32001 = 0;    long feeMoney31001 = 0;    long feeMoney33005 = 0;    for (SettlementDetail settlementDetail : details) {        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_ZS_NOSETTLE.getVal())) {            feeMoney33021 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_YJ_ZS_NOSETTLE.getVal())) {            feeMoney33002 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_YJ_WJTZ.getVal())) {            feeMoney32003 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_NOSETTLE.getVal())) {            feeMoney32001 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_BDYJ_YJ_NOSETTLE.getVal())) {            feeMoney31001 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_YFYJ_ZS_XSG.getVal())) {            feeMoney33005 += settlementDetail.getOassMoney();        }    }    long settlementMoney = feeMoney33021 - feeMoney33002 - feeMoney32003 + feeMoney32001 - feeMoney31001;    long goodCommissionMoney = feeMoney33005 + feeMoney33002 + feeMoney32003 + feeMoney31001;    settlementAmount.setSettlementAmount(settlementMoney);    settlementAmount.setGoodsCommission(goodCommissionMoney);    settlementAmount.setOrderId(orderMain.getOrderId());    settlementAmount.setOrgCode(orderMain.getOrgCode());    settlementAmount.setStationNo(String.valueOf(orderMain.getDeliveryStationNo()));    settlementAmount.setBillTime(new Date());    settlementAmount.setRetSuccess(false);    return settlementAmount;}

该方法逻辑比较简单，就是组装OrderShoudSettlementAmount对象。其中需要计算2个金额，分别是settlementMoney和goodCommissionMoney。

本次需求新增了费项，需要修改该方法。代码修改后如下所示：

private OrderShoudSettlementAmount getOrderShoudSettlementAmount(OrderDTO orderMain, List<SettlementDetail> details) {    OrderShoudSettlementAmount settlementAmount = new OrderShoudSettlementAmount();    // 应结金额=33021-33002-32003+32001-31001+34012-34013    // 货款佣金=33005+33002+32003+31001+34013    long feeMoney33021 = 0;    long feeMoney33002 = 0;    long feeMoney32003 = 0;    long feeMoney32001 = 0;    long feeMoney31001 = 0;    long feeMoney33005 = 0;    // 本次需求新增费项    long feeMoney34012 = 0;    // 本次需求新增费项    long feeMoney34013 = 0;    for (SettlementDetail settlementDetail : details) {        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_ZS_NOSETTLE.getVal())) {            feeMoney33021 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_YJ_ZS_NOSETTLE.getVal())) {            feeMoney33002 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_YJ_WJTZ.getVal())) {            feeMoney32003 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_NOSETTLE.getVal())) {            feeMoney32001 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_BDYJ_YJ_NOSETTLE.getVal())) {            feeMoney31001 += settlementDetail.getOassMoney();        }        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_YFYJ_ZS_XSG.getVal())) {            feeMoney33005 += settlementDetail.getOassMoney();        }        // 本次需求新增费项        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_CHF_XSG_NOSETTLE.getVal())) {            feeMoney34012 += settlementDetail.getOassMoney();        }        // 本次需求新增费项        if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_CHF_YJ_XSG.getVal())) {            feeMoney34013 += settlementDetail.getOassMoney();        }    }    // 本次需求新增费项追加计算 + feeMoney34012 - feeMoney34013    long settlementMoney = feeMoney33021 - feeMoney33002 - feeMoney32003 + feeMoney32001 - feeMoney31001 + feeMoney34012 - feeMoney34013;    // 本次需求新增费项追加计算 + feeMoney34013    long goodCommissionMoney = feeMoney33005 + feeMoney33002 + feeMoney32003 + feeMoney31001 + feeMoney34013;    settlementAmount.setSettlementAmount(settlementMoney);    settlementAmount.setGoodsCommission(goodCommissionMoney);    settlementAmount.setOrderId(orderMain.getOrderId());    settlementAmount.setOrgCode(orderMain.getOrgCode());    settlementAmount.setStationNo(String.valueOf(orderMain.getDeliveryStationNo()));    settlementAmount.setBillTime(new Date());    settlementAmount.setRetSuccess(false);    return settlementAmount;}

二、嗅出代码的坏味道

Martin Fowler在《重构：改善既有代码的设计》一书中列出了22种代码的坏味道：

参照这22种代码的坏味道，我在以上方法代码中嗅出了2种代码的坏味道：

【坏味道1：Duplicated Code（重复的代码）】

for循环中对每种费项的累加操作是重复代码，而且每次新增费项，还得不断增加该重复操作。

for (SettlementDetail settlementDetail : details) {    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_ZS_NOSETTLE.getVal())) {        feeMoney33021 += settlementDetail.getOassMoney();    }    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_FREIGHT_YJ_ZS_NOSETTLE.getVal())) {        feeMoney33002 += settlementDetail.getOassMoney();    }    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_YJ_WJTZ.getVal())) {        feeMoney32003 += settlementDetail.getOassMoney();    }    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_GOODS_NOSETTLE.getVal())) {        feeMoney32001 += settlementDetail.getOassMoney();    }    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_BDYJ_YJ_NOSETTLE.getVal())) {        feeMoney31001 += settlementDetail.getOassMoney();    }    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_YFYJ_ZS_XSG.getVal())) {        feeMoney33005 += settlementDetail.getOassMoney();    }    // 本次需求新增费项    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_CHF_XSG_NOSETTLE.getVal())) {        feeMoney34012 += settlementDetail.getOassMoney();    }    // 本次需求新增费项    if (settlementDetail.getExpenseType().equals(FeeInfoEnum.FEE_INFO_CHF_YJ_XSG.getVal())) {        feeMoney34013 += settlementDetail.getOassMoney();    }}

【坏味道2：Divergent Change（发散式变化）】

Martin Fowler在书中对该坏味道的部分解释如下：

“我们希望软件能够更容易被修改——毕竟软件再怎么说本来就该是“软”的。一旦需要修改，我们希望能够跳到系统的某一点，只在该处做修改。”

现在该方法代码因为新需求开发，修改多处。

其实，除了以上2种代码的坏味道之外，该方法代码最大的问题是面向过程式编码而不是面向对象式的。

为什么这么说呢？

前面提到过该方法的主要作用是组装OrderShoudSettlementAmount对象，那么其逻辑就应该主要体现“组装”，而不是计算金额。计算金额相关逻辑应该抽离到单独的类中，这样既符合面向对象编程思想，也能够消除坏味道2。

三、重构代码

针对前面嗅出的代码坏味道，果断进行重构。重构之后代码如下所示：

private OrderShoudSettlementAmount getOrderShoudSettlementAmount(OrderDTO orderMain, List<SettlementDetail> details) {    OrderShoudSettlementAmount settlementAmount = new OrderShoudSettlementAmount();    Map<Integer, Long> expenseTypeToFeeMoneyMap = Maps.newHashMap();    for (SettlementDetail settlementDetail : details) {        long feeMoney = Optional.ofNullable(expenseTypeToFeeMoneyMap.get(settlementDetail.getExpenseType())).orElse(0L);        feeMoney += Optional.ofNullable(settlementDetail.getOassMoney()).orElse(0L);        expenseTypeToFeeMoneyMap.put(settlementDetail.getExpenseType(), feeMoney);    }    long settlementMoney = SettlementMoneyCalcFeeInfoEnum.calcSettlementMoney(expenseTypeToFeeMoneyMap);    long goodCommissionMoney = GoodCommissionMoneyCalcFeeInfoEnum.calcGoodCommissionMoney(expenseTypeToFeeMoneyMap);    settlementAmount.setSettlementAmount(settlementMoney);    settlementAmount.setGoodsCommission(goodCommissionMoney);    settlementAmount.setOrderId(orderMain.getOrderId());    settlementAmount.setOrgCode(orderMain.getOrgCode());    settlementAmount.setStationNo(String.valueOf(orderMain.getDeliveryStationNo()));    settlementAmount.setBillTime(new Date());    settlementAmount.setRetSuccess(false);    return settlementAmount;}

enum SettlementMoneyCalcFeeInfoEnum {    /**计算项*/    FEE_33021(FeeInfoEnum.FEE_INFO_FREIGHT_ZS_NOSETTLE, "+"),    FEE_33002(FeeInfoEnum.FEE_INFO_FREIGHT_YJ_ZS_NOSETTLE, "-"),    FEE_32003(FeeInfoEnum.FEE_INFO_GOODS_YJ_WJTZ, "-"),    FEE_32001(FeeInfoEnum.FEE_INFO_GOODS_NOSETTLE, "+"),    FEE_31001(FeeInfoEnum.FEE_INFO_BDYJ_YJ_NOSETTLE, "-"),    FEE_34012(FeeInfoEnum.FEE_INFO_CHF_XSG_NOSETTLE, "+"),    FEE_34013(FeeInfoEnum.FEE_INFO_CHF_YJ_XSG, "-");
    private final FeeInfoEnum feeInfoEnum;    private final String symbol;
    SettlementMoneyCalcFeeInfoEnum(FeeInfoEnum feeInfoEnum, String symbol) {        this.feeInfoEnum = feeInfoEnum;        this.symbol = symbol;    }    public static long calcSettlementMoney(Map<Integer, Long> expenseTypeToFeeMoneyMap) {        // 应结金额=33021-33002-32003+32001-31001+34012-34013        long settlementMoney = 0L;        for (SettlementMoneyCalcFeeInfoEnum calcFeeInfoEnum : SettlementMoneyCalcFeeInfoEnum.values()) {            if ("+".equals(calcFeeInfoEnum.symbol)) {                settlementMoney += Optional                        .ofNullable(expenseTypeToFeeMoneyMap.get(calcFeeInfoEnum.feeInfoEnum.getVal()))                        .orElse(0L);            }            if ("-".equals(calcFeeInfoEnum.symbol)) {                settlementMoney -= Optional                        .ofNullable(expenseTypeToFeeMoneyMap.get(calcFeeInfoEnum.feeInfoEnum.getVal()))                        .orElse(0L);            }        }        return settlementMoney;    }}

enum GoodCommissionMoneyCalcFeeInfoEnum {    /**计算项*/    FEE_33005(FeeInfoEnum.FEE_INFO_YFYJ_ZS_XSG),    FEE_33002(FeeInfoEnum.FEE_INFO_FREIGHT_YJ_ZS_NOSETTLE),    FEE_32003(FeeInfoEnum.FEE_INFO_GOODS_YJ_WJTZ),    FEE_31001(FeeInfoEnum.FEE_INFO_BDYJ_YJ_NOSETTLE),    FEE_34013(FeeInfoEnum.FEE_INFO_CHF_YJ_XSG);
    private final FeeInfoEnum feeInfoEnum;
    GoodCommissionMoneyCalcFeeInfoEnum(FeeInfoEnum feeInfoEnum) {        this.feeInfoEnum = feeInfoEnum;    }
    public static long calcGoodCommissionMoney(Map<Integer, Long> expenseTypeToFeeMoneyMap) {        // 货款佣金=33005+33002+32003+31001+34013        long goodCommissionMoney = 0L;        for (GoodCommissionMoneyCalcFeeInfoEnum calcFeeInfoEnum : GoodCommissionMoneyCalcFeeInfoEnum.values()) {            goodCommissionMoney += Optional                    .ofNullable(expenseTypeToFeeMoneyMap.get(calcFeeInfoEnum.feeInfoEnum.getVal()))                    .orElse(0L);        }        return goodCommissionMoney;    }}

四、总结

以上重构的方法代码比较简单，有些人可能会觉得不重构也挺好的，代码可读性也不差，每次修改也就肉眼可见的几个地方，没必要在这上面花费时间。

如果你有以上想法，不妨了解下软件工程中的“破窗效应”：

破窗效应指的是在软件开发过程中，如果存在低质量的代码或设计，如果不及时修复，就会导致其他开发人员也采用同样的低质量方案。这会逐渐升级到更严重的问题，导致软件系统变得难以维护、扩展和改进。因此，在软件开发中，及时解决问题和保持代码质量非常重要，以避免破窗效应对于整个项目造成的负面影响。

同时看看Martin Fowler在《重构：改善既有代码的设计》一书中对重构的部分解释：

重构的每个步骤都很简单，甚至显得有些过于简单：你只需要把某个字段从一个类移到另一个类，把某些代码从一个函数拉出来构成另一个函数，或是在继承体系中把某些代码推上推下就行了。但是，聚沙成塔，这些小小的修改累积起来就可以根本改善设计质量。

重构不仅能够提高代码质量，让代码优雅起来，同时也能让我们学以致用。我们所学的设计思想、原则、模式等理论知识，往往在重构中能够真正实践。

来自同一个声音

CVPR 2026｜Oxygen XR 团队在原生鱼眼高斯泼溅技术上带来新突破

ICML 2026｜InstEmb：面向 Oxygen AIIC 商品知识表征的未来感知指令嵌入

Oxygen AIIC：京东首发面向百亿商品的工业级大模型商品中心全解析

ACL 2026｜GROLE：面向 Oxygen AIIC 工业级模型演进的实例级专家路由增量学习方法