A model-driven development framework for enterprise Web services

The growing scale and complexity of the enterprise computing systems under distributed and heterogeneous environments present new challenges to system development, integration, and maintenance. In this paper, we present a model driven Web service development framework to combat these challenges. The framework capitalizes on the unified modeling language (UML) profile for enterprise distributed object computing (EDOC), MDA (model-driven architecture) and Web services. Within the framework, firstly, a general PIM (platform independent models) is created using the EDOC CCA structural specification and CCA choreography specification which defines the general functions of a system. Secondly, the general PIM is broken down into sub-PIMs according to functional decomposition, each of which can provide service independently and will be implemented in a Web service. Thirdly, all of the PIMs are transformed to Web service interface models for publication and invoking. Afterward, transform each PIM to a BPEL specified Web service orchestration model. Finally, supported by model transform techniques, the sub EDOC PIMs are implemented into Web services on specific platforms. Automatic model transformation is the key to this framework, therefore, the transformation from EDOC CCA models to WSDL specified Web service interface models and the transformation from EDOC CCA models to BPEL specified Web service orchestration models are deeply discussed, and the detailed transformation rules are proposed. A case study is also provided to demonstrate the effectiveness of these rules and the merits of this framework.

针对应用系统ER模型的MDA模型转换方法

MDA是由OMG提出的一种以模型为主要开发产品的软件开发方法。开发人员首先建立与具体技术平台的实现细节无关的高抽象程度的平台无关模型（Platform Independent Model，PIM）。然后，开发人员可以通过模型转换，将高层次的模型逐渐转换成为包含了实现细节的平台相关模型（Platform Specific Model，PSM），直到最终的代码。模型转换的有效性决定了MDA开发方法的效率。模型转换的难点不在于模型的语法映射，而是保证转换过程中模型语义的一致。本文采用E1）C）C作为平台无关模型的描述方法。EDOC是OMG制定的、和具体应用平台无关的、适用于企业分布式系统建模的标准。本文针对EDOC中的实体关系模型建立了从这些模型到J2EE平台模型以及目标代码的模型转换规则。我们还在转换规则中引入了多个设计模式。软件开发人员可以根据对软件的非功能性需求，应用这些规则来选择不同的设计模式，将平台无关的ER模型转换成为J2EE平台上的模型。     

一个MDA支撑工具的设计与实现

MDA是OMG提出的用于解决中间件集成问题的软件开发方法。MDA开发方法以系统模型作为软件开发的主线。在这样的开发过程中,强有力的模型转换支撑工具是MDA思想能够得到广泛应用的关键。而从平台无关模型PIM到平台相关模型PSM的转换工具尤其重要。描述了一个从PIM自动转换到PSM的工具的设计思想。工具使用EDOC profile的一个子集作为PIM的描述方法,使用J2EE作为目标平台。基于一组从PIM到J2EE平台上软件模型的转换规则,工具实现了从PIM到J2EE平台上的PSM的自动转换。