面向对象分析与设计（第3版）（修订版）

• 达行天下

  2022-02-09
  每一种编程风格都基于它自己的概念框架。对于所有面向对象的东西，概念框架就是对象模型。这个模型有四个主要要素：（1）抽象；（2）封装；（3）模块化；（4）层次结构。所谓“主要”，指的是如果一个模型不具备这些元素之一，就不是面向对象的。对象模型有三个次要要素：（1）类型；（2）并发；（3）持久。所谓“次要”，指的是这些要素是对象模型的有用组成部分，但不是本质的。
• 达行天下

  2022-02-08
  关于复杂系统中基础组件的实质，我们的经验表明：“选择哪些作为系统的基础组件相对来说比较随意，这在很大程度上取决于系统观察者的判断。”对于一个观察者来说很基础的东西，对另一个观察者可能具有很高的抽象层次。
• dhcn

  2013-05-17
  在我们见过的最不正常的一个案例中，业务机构的人认为与开发人员沟通是一件丢人的事情，有可能对他们的事业产生不好的影响。
• gao

  2011-04-05
  The part of software development that will go away is the crafting of conceptual structures; the part that can go away is the labor of expressing them.The UML has numerous types of diagrams, each providing a certain view of your system.Across all diagrams, all entities with the same name are considered to be references to the same modeal item.UML can be classified into two groups:structure diagrams and behavior diagrams.Behavior Diagrams-User Case Diagram-Activity Diagram-State Machine Diagram-Interaction Diagrams.. Sequence Diagram.. Communication Diagram.. Interaction Overview Diagram.. Timing Diagramforward-engineeringreverse-engineeringThe Conceptual modelcaptures the system in terms of the domain entities that exist(or will exist) and their association wi...
• gao

  2011-04-03
  Through the object concept, a child comes to realize that objects have a permanence and identity apart from any operations on them.what is an Object?an object represents an individual, identifiable item, unit, or entity, either real or abstract, with a well-defined role in the problem domain.control objects--the ones that unite courses of events and thus will carry on communication with other objects.Some objects may have crisp conceptual boundaries yet represent intangible events or processes.An object has state, exhibits some well-defined behavior, and has a unique identity.Some objects may be tangible yet have fuzzy physical boundaries.attributes such as beauty or color are not objects, nor are emotions such as love and anger. On the other hand, these things are...