专业英语

软件架构重用

软件架构重用是一个解释性、交互式和反复迭代的过程，包括了多项活动。信息提取通过分析系统现有设计和实现工件来构造它的模型。其结果用于在后续活动中构造系统的视图。数据库构建活动把模型中包含的元素和关系转换为数据库中的标准存储格式。视图融合活动包括定义和操作数据库中存储的信息，理顺、加强并建立起元素之间的连接。重构由两个主要活动组成；可视化和交互及模式定义和识别。前者提供了一种让用户操作架构元素的机制，后者则提供了用于架构重构的设施。

Software architecture reconstruction is an interpretive, interactive, and iterative process including many activities. Information extraction involves analyzing a system's existing design and implementation artifacts to construct a model of it. The result is used in the following activities to construct a view of the system. The database construction activity converts the elements and relations contained in the view into a standard format for storage in a database. The view fusion activity involves defining and manipulating the information stored in database to reconcile, augment, and establish connections between the elements. Reconstruction consists of two primary activities: visualization and interaction and pattern definition and recognition. The former provides a mechanism for the user to manipulate architectural elements, and the latter provides facilities for architecture reconstruction.

系统架构是一个系统的一种表示，包含了功能到软硬件构件的映射、软件架构到硬件架构的映射以及对于这些组件人机交互的关注。也就是说，系统架构关注于整个系统，包括硬件、软件和使用者。软件架构结构根据其所展示元素的广义性质，可以被分为三个主要类别。 1）模块结构将决策体现为一组需要被构建或采购的代码或数据单元。 2）构件连接器结构将决策体现为系统如何被结构化为一组具有运行时行为和交互的元素。 3）分配结构将决策体现为系统如何在其环境中关联到非软件结构，如CPU、文件系统、网络、开发团队等。

A system's architecture is a representation of a system in which there is a mapping of functionality onto hardware and software components, a mapping of the software architecture onto the hardware architecture. and a concern for the human interaction with these components. That is, system architecture is concerned with a total system, including hardware. software, and humans. Software architectural structures can be divided into three major categories, depending on the broad nature of the elements they show.1）Module structures embody decisions as a set of code or data units that have to be constructed or procured.2）Component-and-connector structures embody decisions as to how the system is to be structured as set of elements that have runtime behavior and interactions.3）Allocation structures embody decisions as to how the system will relate to non software structures in its environment(such as CPUs, file systems, networks, development teams, etc.).

架构设计的目标是确定应用软件的哪些部分将分配到何种硬件。识别出正在开发系统的主要软件构件并分配到系统将要运行的硬件构件。所有软件系统可分为四项基本功能。第一项是数据存储。大多数信息系统需要数据进行存储并检索，不论是一个小文件，比如一个字处理器产生的一个备忘录，还是一个大型数据库，比如存储一个企业会计记录的数据库。第二项功能是数据访问逻辑，处理过程需要访问数据，这通常是指用SQL进行数据库查询。第三项功能是应用程序逻辑，这些逻辑通过数据流图，用例和功能需求来记录。第四项功能是表示逻辑，给用户显示信息并接收用户命令。一个系统的三类主要硬件构件是客户机、服务器和网络。

The objective of architecture design is to determine what parts of the application software will be assigned to what hardware. The major software components of the system being developed have to be identified and then allocated to the various hardware components on which the system will operate. All software systems can be divided into four basic functions. The first is data storage. Most information systems require data to be stored and retrieved, whether a small file,such as a memo produced by a word processor, or a large database, such as one that stores an organization’s accounting records.The second function is the data access logic, the processing required to access data, which often means database queries in Structured Query Language. The third function is the application logic, which is the logic documented in the DFDs, use cases,and functional requirements.The fourth function is the presentation logic,the display of information to the user and the acceptance of the user’s commands.The three primary hardware components of a system are clients,servers,and network.