网站维护推广怎么做,单页网站搭建,网站怎么做快照,美食网站程序如何利用UML进行领域建模
领域建模是通过创建抽象模型来反映业务领域中的核心概念、实体及其之间的关系。UML#xff08;统一建模语言#xff09;是进行领域建模的常用工具#xff0c;它能帮助我们可视化地设计系统架构和业务逻辑。在这篇讲解中#xff0c;我们将详细解释…如何利用UML进行领域建模
领域建模是通过创建抽象模型来反映业务领域中的核心概念、实体及其之间的关系。UML统一建模语言是进行领域建模的常用工具它能帮助我们可视化地设计系统架构和业务逻辑。在这篇讲解中我们将详细解释如何使用UML进行领域建模包括如何识别实体、类、实例处理多对多关系以及完善业务规则和建立领域词汇表。
领域建模的基本概念
在开始领域建模之前先了解几个重要概念
领域对象Domain Object表示业务领域中的某个事物或概念如“订单”、“商品”等。实体Entity具有唯一标识的对象代表业务中的数据。例如“客户”是一个实体每个客户都有一个唯一的ID。类Class实体的抽象描述定义了实体的属性和行为。例如Customer 类包括客户的基本信息和相关操作。实例Instance类的具体对象。比如 Customer 类的一个实例可以是具体的某个客户“张三”。聚合Aggregate一组相关的实体和值对象的集合。聚合可以用来管理复杂业务逻辑保证数据一致性。
使用UML类图进行领域建模的步骤
1. 识别主要实体
首先识别系统中的核心实体。以一个在线书店为例核心实体包括
客户Customer存储客户信息。订单Order记录订单的详细信息。商品Product表示在系统中销售的商品。
我们可以通过UML类图展示这些实体及其属性和操作 #mermaid-svg-w9SNzJTlmcrYPsRN {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-w9SNzJTlmcrYPsRN .error-icon{fill:#552222;}#mermaid-svg-w9SNzJTlmcrYPsRN .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-w9SNzJTlmcrYPsRN .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-w9SNzJTlmcrYPsRN .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-w9SNzJTlmcrYPsRN .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-w9SNzJTlmcrYPsRN .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-w9SNzJTlmcrYPsRN .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-w9SNzJTlmcrYPsRN .marker{fill:#333333;stroke:#333333;}#mermaid-svg-w9SNzJTlmcrYPsRN .marker.cross{stroke:#333333;}#mermaid-svg-w9SNzJTlmcrYPsRN svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-w9SNzJTlmcrYPsRN g.classGroup text{fill:#9370DB;fill:#131300;stroke:none;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:10px;}#mermaid-svg-w9SNzJTlmcrYPsRN g.classGroup text .title{font-weight:bolder;}#mermaid-svg-w9SNzJTlmcrYPsRN .nodeLabel,#mermaid-svg-w9SNzJTlmcrYPsRN .edgeLabel{color:#131300;}#mermaid-svg-w9SNzJTlmcrYPsRN .edgeLabel .label rect{fill:#ECECFF;}#mermaid-svg-w9SNzJTlmcrYPsRN .label text{fill:#131300;}#mermaid-svg-w9SNzJTlmcrYPsRN .edgeLabel .label span{background:#ECECFF;}#mermaid-svg-w9SNzJTlmcrYPsRN .classTitle{font-weight:bolder;}#mermaid-svg-w9SNzJTlmcrYPsRN .node rect,#mermaid-svg-w9SNzJTlmcrYPsRN .node circle,#mermaid-svg-w9SNzJTlmcrYPsRN .node ellipse,#mermaid-svg-w9SNzJTlmcrYPsRN .node polygon,#mermaid-svg-w9SNzJTlmcrYPsRN .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-w9SNzJTlmcrYPsRN .divider{stroke:#9370DB;stroke:1;}#mermaid-svg-w9SNzJTlmcrYPsRN g.clickable{cursor:pointer;}#mermaid-svg-w9SNzJTlmcrYPsRN g.classGroup rect{fill:#ECECFF;stroke:#9370DB;}#mermaid-svg-w9SNzJTlmcrYPsRN g.classGroup line{stroke:#9370DB;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN .classLabel .box{stroke:none;stroke-width:0;fill:#ECECFF;opacity:0.5;}#mermaid-svg-w9SNzJTlmcrYPsRN .classLabel .label{fill:#9370DB;font-size:10px;}#mermaid-svg-w9SNzJTlmcrYPsRN .relation{stroke:#333333;stroke-width:1;fill:none;}#mermaid-svg-w9SNzJTlmcrYPsRN .dashed-line{stroke-dasharray:3;}#mermaid-svg-w9SNzJTlmcrYPsRN #compositionStart,#mermaid-svg-w9SNzJTlmcrYPsRN .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #compositionEnd,#mermaid-svg-w9SNzJTlmcrYPsRN .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #dependencyStart,#mermaid-svg-w9SNzJTlmcrYPsRN .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #dependencyStart,#mermaid-svg-w9SNzJTlmcrYPsRN .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #extensionStart,#mermaid-svg-w9SNzJTlmcrYPsRN .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #extensionEnd,#mermaid-svg-w9SNzJTlmcrYPsRN .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #aggregationStart,#mermaid-svg-w9SNzJTlmcrYPsRN .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN #aggregationEnd,#mermaid-svg-w9SNzJTlmcrYPsRN .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-w9SNzJTlmcrYPsRN .edgeTerminals{font-size:11px;}#mermaid-svg-w9SNzJTlmcrYPsRN :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;} Customer id: String name: String email: String placeOrder() Order orderId: String date: Date status: String addProduct() Product productId: String name: String price: Double addToOrder() 2. 通过多重性确定实体之间的关联
多重性描述两个实体之间的数量关系。以“客户”和“订单”为例客户和订单之间可以通过四个问题来确定关联的多重性
一个客户最多可以下多少个订单 一个客户可以下多个订单最多为 *。一个客户最少可以下多少个订单 客户可能不下订单因此最少为 0。一个订单最多可以有多少个客户 每个订单只能由一个客户拥有因此最多为 1。一个订单最少可以有多少个客户 每个订单必须有一个客户因此最少为 1。
通过这些问题我们可以确定“客户”和“订单”之间是一对多的关系 #mermaid-svg-W4P0TTokh1OMwOUK {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-W4P0TTokh1OMwOUK .error-icon{fill:#552222;}#mermaid-svg-W4P0TTokh1OMwOUK .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-W4P0TTokh1OMwOUK .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-W4P0TTokh1OMwOUK .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-W4P0TTokh1OMwOUK .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-W4P0TTokh1OMwOUK .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-W4P0TTokh1OMwOUK .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-W4P0TTokh1OMwOUK .marker{fill:#333333;stroke:#333333;}#mermaid-svg-W4P0TTokh1OMwOUK .marker.cross{stroke:#333333;}#mermaid-svg-W4P0TTokh1OMwOUK svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-W4P0TTokh1OMwOUK g.classGroup text{fill:#9370DB;fill:#131300;stroke:none;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:10px;}#mermaid-svg-W4P0TTokh1OMwOUK g.classGroup text .title{font-weight:bolder;}#mermaid-svg-W4P0TTokh1OMwOUK .nodeLabel,#mermaid-svg-W4P0TTokh1OMwOUK .edgeLabel{color:#131300;}#mermaid-svg-W4P0TTokh1OMwOUK .edgeLabel .label rect{fill:#ECECFF;}#mermaid-svg-W4P0TTokh1OMwOUK .label text{fill:#131300;}#mermaid-svg-W4P0TTokh1OMwOUK .edgeLabel .label span{background:#ECECFF;}#mermaid-svg-W4P0TTokh1OMwOUK .classTitle{font-weight:bolder;}#mermaid-svg-W4P0TTokh1OMwOUK .node rect,#mermaid-svg-W4P0TTokh1OMwOUK .node circle,#mermaid-svg-W4P0TTokh1OMwOUK .node ellipse,#mermaid-svg-W4P0TTokh1OMwOUK .node polygon,#mermaid-svg-W4P0TTokh1OMwOUK .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-W4P0TTokh1OMwOUK .divider{stroke:#9370DB;stroke:1;}#mermaid-svg-W4P0TTokh1OMwOUK g.clickable{cursor:pointer;}#mermaid-svg-W4P0TTokh1OMwOUK g.classGroup rect{fill:#ECECFF;stroke:#9370DB;}#mermaid-svg-W4P0TTokh1OMwOUK g.classGroup line{stroke:#9370DB;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK .classLabel .box{stroke:none;stroke-width:0;fill:#ECECFF;opacity:0.5;}#mermaid-svg-W4P0TTokh1OMwOUK .classLabel .label{fill:#9370DB;font-size:10px;}#mermaid-svg-W4P0TTokh1OMwOUK .relation{stroke:#333333;stroke-width:1;fill:none;}#mermaid-svg-W4P0TTokh1OMwOUK .dashed-line{stroke-dasharray:3;}#mermaid-svg-W4P0TTokh1OMwOUK #compositionStart,#mermaid-svg-W4P0TTokh1OMwOUK .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #compositionEnd,#mermaid-svg-W4P0TTokh1OMwOUK .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #dependencyStart,#mermaid-svg-W4P0TTokh1OMwOUK .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #dependencyStart,#mermaid-svg-W4P0TTokh1OMwOUK .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #extensionStart,#mermaid-svg-W4P0TTokh1OMwOUK .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #extensionEnd,#mermaid-svg-W4P0TTokh1OMwOUK .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #aggregationStart,#mermaid-svg-W4P0TTokh1OMwOUK .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK #aggregationEnd,#mermaid-svg-W4P0TTokh1OMwOUK .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-W4P0TTokh1OMwOUK .edgeTerminals{font-size:11px;}#mermaid-svg-W4P0TTokh1OMwOUK :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;} places 1 0..* Customer Order 类似地我们可以用相同的方法分析订单和商品之间的多重性。订单和商品之间存在多对多关系一个订单可以包含多个商品一个商品可以出现在多个订单中。
3. 如何将多对多关系拆分为一对多关系
在领域建模中处理多对多关系可能会比较复杂。为了简化设计我们通常通过引入一个中间实体将多对多关系拆分为两个一对多关系。
示例订单和商品的多对多关系
假设“订单”和“商品”之间存在多对多关系一个订单可以包含多个商品一个商品也可以出现在多个订单中。为了更清晰地表示这一关系我们可以引入一个中间实体OrderItem表示订单中的每个商品及其数量。
通过将Order和Product的多对多关系拆分成两个一对多关系我们可以这样表示 #mermaid-svg-c91PL3aMwUl2n7oN {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-c91PL3aMwUl2n7oN .error-icon{fill:#552222;}#mermaid-svg-c91PL3aMwUl2n7oN .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-c91PL3aMwUl2n7oN .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-c91PL3aMwUl2n7oN .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-c91PL3aMwUl2n7oN .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-c91PL3aMwUl2n7oN .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-c91PL3aMwUl2n7oN .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-c91PL3aMwUl2n7oN .marker{fill:#333333;stroke:#333333;}#mermaid-svg-c91PL3aMwUl2n7oN .marker.cross{stroke:#333333;}#mermaid-svg-c91PL3aMwUl2n7oN svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-c91PL3aMwUl2n7oN g.classGroup text{fill:#9370DB;fill:#131300;stroke:none;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:10px;}#mermaid-svg-c91PL3aMwUl2n7oN g.classGroup text .title{font-weight:bolder;}#mermaid-svg-c91PL3aMwUl2n7oN .nodeLabel,#mermaid-svg-c91PL3aMwUl2n7oN .edgeLabel{color:#131300;}#mermaid-svg-c91PL3aMwUl2n7oN .edgeLabel .label rect{fill:#ECECFF;}#mermaid-svg-c91PL3aMwUl2n7oN .label text{fill:#131300;}#mermaid-svg-c91PL3aMwUl2n7oN .edgeLabel .label span{background:#ECECFF;}#mermaid-svg-c91PL3aMwUl2n7oN .classTitle{font-weight:bolder;}#mermaid-svg-c91PL3aMwUl2n7oN .node rect,#mermaid-svg-c91PL3aMwUl2n7oN .node circle,#mermaid-svg-c91PL3aMwUl2n7oN .node ellipse,#mermaid-svg-c91PL3aMwUl2n7oN .node polygon,#mermaid-svg-c91PL3aMwUl2n7oN .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-c91PL3aMwUl2n7oN .divider{stroke:#9370DB;stroke:1;}#mermaid-svg-c91PL3aMwUl2n7oN g.clickable{cursor:pointer;}#mermaid-svg-c91PL3aMwUl2n7oN g.classGroup rect{fill:#ECECFF;stroke:#9370DB;}#mermaid-svg-c91PL3aMwUl2n7oN g.classGroup line{stroke:#9370DB;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN .classLabel .box{stroke:none;stroke-width:0;fill:#ECECFF;opacity:0.5;}#mermaid-svg-c91PL3aMwUl2n7oN .classLabel .label{fill:#9370DB;font-size:10px;}#mermaid-svg-c91PL3aMwUl2n7oN .relation{stroke:#333333;stroke-width:1;fill:none;}#mermaid-svg-c91PL3aMwUl2n7oN .dashed-line{stroke-dasharray:3;}#mermaid-svg-c91PL3aMwUl2n7oN #compositionStart,#mermaid-svg-c91PL3aMwUl2n7oN .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #compositionEnd,#mermaid-svg-c91PL3aMwUl2n7oN .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #dependencyStart,#mermaid-svg-c91PL3aMwUl2n7oN .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #dependencyStart,#mermaid-svg-c91PL3aMwUl2n7oN .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #extensionStart,#mermaid-svg-c91PL3aMwUl2n7oN .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #extensionEnd,#mermaid-svg-c91PL3aMwUl2n7oN .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #aggregationStart,#mermaid-svg-c91PL3aMwUl2n7oN .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN #aggregationEnd,#mermaid-svg-c91PL3aMwUl2n7oN .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-c91PL3aMwUl2n7oN .edgeTerminals{font-size:11px;}#mermaid-svg-c91PL3aMwUl2n7oN :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;} contains 1 0..* partOf 1 0..* OrderItem quantity: int price: Double Order Product 一个Order订单可以包含多个OrderItem订单项每个订单项表示订单中的某个商品及其数量。一个Product商品可以出现在多个OrderItem中表示同一个商品可以出现在不同的订单中。
为什么要拆分多对多关系
存储额外信息引入OrderItem不仅简化了关联还允许我们存储商品的数量、价格等额外信息。如果我们仅仅用多对多关系这些信息就无法保存。便于管理拆分多对多关系可以让模型更加简洁易于维护同时也有助于优化数据库的查询性能。
什么时候不需要拆分
如果多对多关系仅仅是简单的关联没有需要存储的额外信息那么可以直接使用多对多关系而不需要拆分为一对多。例如学生和课程之间的多对多关系可以直接表示为学生选修多个课程课程也可以有多个学生选修。 #mermaid-svg-y9KdjdzdvSSn9v8V {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-y9KdjdzdvSSn9v8V .error-icon{fill:#552222;}#mermaid-svg-y9KdjdzdvSSn9v8V .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-y9KdjdzdvSSn9v8V .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-y9KdjdzdvSSn9v8V .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-y9KdjdzdvSSn9v8V .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-y9KdjdzdvSSn9v8V .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-y9KdjdzdvSSn9v8V .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-y9KdjdzdvSSn9v8V .marker{fill:#333333;stroke:#333333;}#mermaid-svg-y9KdjdzdvSSn9v8V .marker.cross{stroke:#333333;}#mermaid-svg-y9KdjdzdvSSn9v8V svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-y9KdjdzdvSSn9v8V g.classGroup text{fill:#9370DB;fill:#131300;stroke:none;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:10px;}#mermaid-svg-y9KdjdzdvSSn9v8V g.classGroup text .title{font-weight:bolder;}#mermaid-svg-y9KdjdzdvSSn9v8V .nodeLabel,#mermaid-svg-y9KdjdzdvSSn9v8V .edgeLabel{color:#131300;}#mermaid-svg-y9KdjdzdvSSn9v8V .edgeLabel .label rect{fill:#ECECFF;}#mermaid-svg-y9KdjdzdvSSn9v8V .label text{fill:#131300;}#mermaid-svg-y9KdjdzdvSSn9v8V .edgeLabel .label span{background:#ECECFF;}#mermaid-svg-y9KdjdzdvSSn9v8V .classTitle{font-weight:bolder;}#mermaid-svg-y9KdjdzdvSSn9v8V .node rect,#mermaid-svg-y9KdjdzdvSSn9v8V .node circle,#mermaid-svg-y9KdjdzdvSSn9v8V .node ellipse,#mermaid-svg-y9KdjdzdvSSn9v8V .node polygon,#mermaid-svg-y9KdjdzdvSSn9v8V .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-y9KdjdzdvSSn9v8V .divider{stroke:#9370DB;stroke:1;}#mermaid-svg-y9KdjdzdvSSn9v8V g.clickable{cursor:pointer;}#mermaid-svg-y9KdjdzdvSSn9v8V g.classGroup rect{fill:#ECECFF;stroke:#9370DB;}#mermaid-svg-y9KdjdzdvSSn9v8V g.classGroup line{stroke:#9370DB;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V .classLabel .box{stroke:none;stroke-width:0;fill:#ECECFF;opacity:0.5;}#mermaid-svg-y9KdjdzdvSSn9v8V .classLabel .label{fill:#9370DB;font-size:10px;}#mermaid-svg-y9KdjdzdvSSn9v8V .relation{stroke:#333333;stroke-width:1;fill:none;}#mermaid-svg-y9KdjdzdvSSn9v8V .dashed-line{stroke-dasharray:3;}#mermaid-svg-y9KdjdzdvSSn9v8V #compositionStart,#mermaid-svg-y9KdjdzdvSSn9v8V .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #compositionEnd,#mermaid-svg-y9KdjdzdvSSn9v8V .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #dependencyStart,#mermaid-svg-y9KdjdzdvSSn9v8V .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #dependencyStart,#mermaid-svg-y9KdjdzdvSSn9v8V .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #extensionStart,#mermaid-svg-y9KdjdzdvSSn9v8V .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #extensionEnd,#mermaid-svg-y9KdjdzdvSSn9v8V .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #aggregationStart,#mermaid-svg-y9KdjdzdvSSn9v8V .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V #aggregationEnd,#mermaid-svg-y9KdjdzdvSSn9v8V .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-y9KdjdzdvSSn9v8V .edgeTerminals{font-size:11px;}#mermaid-svg-y9KdjdzdvSSn9v8V :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;} enrolls 1 0..* offeredTo 1 0..* Student Course 这种情况下关系相对简单可以直接使用不需要引入中间实体。
4. 添加业务逻辑与操作
除了定义实体和关联还可以为实体添加操作以反映实际的业务逻辑。例如客户下订单、订单添加商品等操作都可以通过UML类图中的方法来表示 #mermaid-svg-iVjy9Yvn198rWgOS {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-iVjy9Yvn198rWgOS .error-icon{fill:#552222;}#mermaid-svg-iVjy9Yvn198rWgOS .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-iVjy9Yvn198rWgOS .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-iVjy9Yvn198rWgOS .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-iVjy9Yvn198rWgOS .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-iVjy9Yvn198rWgOS .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-iVjy9Yvn198rWgOS .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-iVjy9Yvn198rWgOS .marker{fill:#333333;stroke:#333333;}#mermaid-svg-iVjy9Yvn198rWgOS .marker.cross{stroke:#333333;}#mermaid-svg-iVjy9Yvn198rWgOS svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-iVjy9Yvn198rWgOS g.classGroup text{fill:#9370DB;fill:#131300;stroke:none;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:10px;}#mermaid-svg-iVjy9Yvn198rWgOS g.classGroup text .title{font-weight:bolder;}#mermaid-svg-iVjy9Yvn198rWgOS .nodeLabel,#mermaid-svg-iVjy9Yvn198rWgOS .edgeLabel{color:#131300;}#mermaid-svg-iVjy9Yvn198rWgOS .edgeLabel .label rect{fill:#ECECFF;}#mermaid-svg-iVjy9Yvn198rWgOS .label text{fill:#131300;}#mermaid-svg-iVjy9Yvn198rWgOS .edgeLabel .label span{background:#ECECFF;}#mermaid-svg-iVjy9Yvn198rWgOS .classTitle{font-weight:bolder;}#mermaid-svg-iVjy9Yvn198rWgOS .node rect,#mermaid-svg-iVjy9Yvn198rWgOS .node circle,#mermaid-svg-iVjy9Yvn198rWgOS .node ellipse,#mermaid-svg-iVjy9Yvn198rWgOS .node polygon,#mermaid-svg-iVjy9Yvn198rWgOS .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-iVjy9Yvn198rWgOS .divider{stroke:#9370DB;stroke:1;}#mermaid-svg-iVjy9Yvn198rWgOS g.clickable{cursor:pointer;}#mermaid-svg-iVjy9Yvn198rWgOS g.classGroup rect{fill:#ECECFF;stroke:#9370DB;}#mermaid-svg-iVjy9Yvn198rWgOS g.classGroup line{stroke:#9370DB;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS .classLabel .box{stroke:none;stroke-width:0;fill:#ECECFF;opacity:0.5;}#mermaid-svg-iVjy9Yvn198rWgOS .classLabel .label{fill:#9370DB;font-size:10px;}#mermaid-svg-iVjy9Yvn198rWgOS .relation{stroke:#333333;stroke-width:1;fill:none;}#mermaid-svg-iVjy9Yvn198rWgOS .dashed-line{stroke-dasharray:3;}#mermaid-svg-iVjy9Yvn198rWgOS #compositionStart,#mermaid-svg-iVjy9Yvn198rWgOS .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #compositionEnd,#mermaid-svg-iVjy9Yvn198rWgOS .composition{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #dependencyStart,#mermaid-svg-iVjy9Yvn198rWgOS .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #dependencyStart,#mermaid-svg-iVjy9Yvn198rWgOS .dependency{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #extensionStart,#mermaid-svg-iVjy9Yvn198rWgOS .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #extensionEnd,#mermaid-svg-iVjy9Yvn198rWgOS .extension{fill:#333333!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #aggregationStart,#mermaid-svg-iVjy9Yvn198rWgOS .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS #aggregationEnd,#mermaid-svg-iVjy9Yvn198rWgOS .aggregation{fill:#ECECFF!important;stroke:#333333!important;stroke-width:1;}#mermaid-svg-iVjy9Yvn198rWgOS .edgeTerminals{font-size:11px;}#mermaid-svg-iVjy9Yvn198rWgOS :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;} Customer placeOrder(order: Order) Order addProduct(product: Product, quantity: int) 通过这些方法类不仅仅表示数据结构还能表现出业务的动态行为。
5. 完善业务规则和建立词汇表
领域建模不仅仅是构建数据模型还需要完善业务规则和建立领域词汇表。 完善业务规则通过业务规则确保模型能够正确反映实际的业务需求。例如一个订单只有在支付完成后才能发货。这种业务规则可以通过在模型中加入约束来表示。 建立领域词汇表领域词汇表确保团队对业务术语的理解一致。例如“订单”、“商品”、“客户”等术语的定义要统一以免在团队沟通中产生歧义。
6. 领域建模的模块化和实践
当模型变得复杂时可以通过将模型划分为多个模块来简化设计。例如将客户模块、订单模块和商品模块分开管理有助于减少复杂性使系统更加灵活和可维护。
完成模型之后建议通过以下两项实践来提升模型的准确性
完善业务规则通过与业务专家讨论进一步完善模型中的业务逻辑。建立领域词汇表确保团队对领域术语的理解一致。
总结
利用UML进行领域建模时识别核心实体、定义实体间的关联关系、处理复杂的多对多关系都是非常重要的步骤。通过引入中间实体复杂的多对多关系可以被拆分成两个简单的一对多关系。
