Active Declarative Integration Rules for Developing Distributed Multi-Tiered Applications

虽然有工具，允许从分布式源访问信息和数据，有一个强烈的需要，开发一个语义层的顶部，这样的工具，以处理从分布式软件组件构建的应用程序的挑战性要求。本研究旨在探讨整合规则语言的设计，以及发展一个中间层的规则处理架构，以整合分散式的黑盒元件。集成规则是活动的，指定对象如何对事件做出反应，而声明性的，指定应在哪些条件下执行已定义的操作。这些规则在集成框架中使用，该框架封装了与分布式组件互连相关的处理逻辑。用户界面允许用户以图形方式指定处理逻辑，该逻辑会自动转换为适当的集成规则。集成规则在规则引擎中执行，该规则引擎被设计为使用CORBA（公共对象请求代理体系结构）和Java编程语言构建分布式对象计算的公认优势。集成规则的表达性和使用情况进行评估的案例研究比较集成组件使用命令式代码与使用集成规则。这样一个规则处理环境的发展具有直接的相关性的分布式应用程序，如电子商务，工程设计和制造，和基于Web的应用程序，一般的集成。这种集成框架提供了一种快速的方法来构建多层应用程序，将处理逻辑与客户端和数据源分离。

Although there are tools that allow access to information and data from distributed sources, there is a strong need to develop a semantic layer on top of such tools to deal with the challenging requirements of applications built from distributed software components. This research is investigating the design of an integration rule language and the development of a middle-tier, rule-processing framework for the integration of distributed, black-box components. Integration rules are active, specifying how objects react to events, and declarative, specifying the conditions under which the defined action should be executed. The rules are used within an integration framework that encapsulates the processing logic associated with the interconnection of distributed components. A user interface allows the user to graphically specify the processing logic, which is automatically translated into the appropriate integration rules. Integration rules are executed within a rule engine, which is designed to build on the recognized strengths of distributed object computing with CORBA (Common Object Request Broker Architecture) and the Java programming language. The expressiveness and use of integration rules are evaluated by case study comparisons of integrating components using imperative code versus the use of integration rules. The development of such a rule-processing environment has an immediate relevance to the integration of distributed applications, such as electronic commerce, engineering design and manufacturing, and Web-based applications, in general. This integration framework provides a rapid approach to the construction of multi-tiered applications that separate processing logic from client and data sources.