軟件工程-12領(lǐng)域模型-概念的可視化(文件)
【正文】 ible——盡量少加 Need to know To reconstruct a sale, print a receipt, or calculate a sale total. the requirements do not suggest that any such relationship is needed. 添加關(guān)聯(lián) 從常用關(guān)聯(lián)列表中導出的關(guān)聯(lián) 由此開始 高優(yōu)先級關(guān)聯(lián) ? A is a physical or logical part of B. ? A is physically or logically contained in/on B. ? A is recorded in B. 關(guān)聯(lián)指南 集中于需要保存一定時間的關(guān)系（ Need to know關(guān)聯(lián)） 提取概念類比識別關(guān)聯(lián)更重要 太多的關(guān)聯(lián)會使領(lǐng)域模型更混亂 ?耗時，而效果遞減 ?避免顯示冗余或可導出的關(guān)聯(lián) 角色 Each end of an association is called a role. Roles may optionally have: ? name ? multiplicity expression ? Navigability（導航） Multiplicity The multiplicity value municates(表明 ) how many instances can be validly associated with another, at a particular moment, rather than over a span of time. ?一夫一妻制中。. ? Separate instances of PhoneNumber that contain the same number. ? Separate instances of Address that contain the same address. only valuebased parisons are relevant. Conceptual class it is meaningful to distinguish (by identity) between two separate instances of a Person whose names are both Jill Smith pare the memory addresses of Person instances, 屬性 (data type) or 概念類 ? Make it an attribute ? if it is naturally thought of as number, string, boolean, date, or time (and so on) Otherwise ? represent it as a separate conceptual class. If in doubt ? define something as a separate conceptual class rather than as anattribute. 屬性 primitive data type ? such as a number or string nonprimitive data type. ? PhoneNumber ? also known as value objects ? a nonprimitive class ? Data Type Classes 促銷價 Universal Product Code (UPC) or European Article Number (EAN) 以前作為 Primitive data type的在以下情況下可能表示為 Nonprimitive type 應用以上原則 盡管實例的唯一身份無意義，但仍值得作為單獨的類 item identifier?nonprimitive ItemID ? abstraction ? subparts price and amount attributes? nonprimitive Quantity or Money classes The address attribute? a nonprimitive Address There is no correct answer ? A domain model is a tool of munication。 in the UML ? 兩種常用格式 ? Paidby ? PaidBy default direction to read an association name is left to right or top to bottom ? not a UML default, but a mon convention. Multiple Associations Between Two Types Unfettable Relationships in the Store Applying the Category of Associations Checklist 添加關(guān)聯(lián) 領(lǐng)域模型 ——添加屬性 包含什么
公司管理相關(guān)推薦
鄂ICP備17016276號-1