VERA: Verifiable Aspect Models for Middleware Product Families (Visiting Fellowship)

VERA项目的总体目标是开发一个建模框架，用于验证与中间件家族相关的方面模型的组成。中间件正在成为构建（通常是复杂的）分布式应用程序和服务中越来越重要的技术。中间件的作用是掩盖异构性和分布性问题，并为应用程序开发人员提供更抽象和透明的编程模型。然而，近年来，提供全面的中间件平台变得更加困难，这主要是由于异构性水平的显著上升。除了传统的异质性方面（语言、平台等），中间件提供商还必须处理应用领域（普及、多媒体、移动的、网格等）日益增长的异构性。以及部署环境（无线、有线、ad-hoc等）中异构性的类似增加。此外，还需要支持安全性和可靠性等领域的各种非功能性要求，例如在普及计算等领域出现了更专业的解决方案。现在很明显，中间件提供商正在努力解决这种极端的异构性，而不是提供过于臃肿和复杂的平台来处理可能使用它们的各种情况。同样明显的是，这是不令人满意的，需要一个重大的范式转变，以满足这种不断变化的操作条件。中间件社区正在对这些挑战作出反应，现在有强烈的兴趣，反射中间件作为一种技术，以支持更多的可配置性，甚至可重新配置。为了这个建议的目的，我们专注于可配置的中间件的问题，特别是，如何使用反射提供的固有支持，可以生成中间件家族。然而，在处理反思所提供的灵活性方面存在着一个复杂因素。因此，当务之急是在反射中间件的发展，我们还研究工具和技术，支持自动或半自动生成的中间件系列从更高层次的规范。在这个项目中，我们建议研究三个技术领域的婚姻，以应对这一挑战：1。如上面讨论的反射中间件;2.模型驱动工程（MDE），支持从模型（在我们的情况下是中间件）自动构建复杂软件;3.面向对象的软件开发（AOSD），在模型和最终平台方面提供关注点的自然分离。这需要不同社区之间的密切合作。兰开斯特很幸运，在（反射）中间件和AOSD领域拥有国际领先的活动。该提案涉及通过引入Robert France教授作为访问研究员到该部门进行为期5个月的工作来补充这些技能，以完成我们对这三个领域的覆盖（Robert是MDE的领先研究员）。

The overall aim of the VERA project is to develop a modelling framework for verifiable composition of aspect models pertaining to middleware families. Middleware is emerging as an increasingly important technology in the construction of (often complex) distributed applications and services. The role of middleware is to mask out problems of heterogeneity and distribution and to provide a more abstract and transparent programming model to application developers. However, in recent years it has become much more difficult to provide comprehensive middleware platforms largely due to the significant rise in levels of heterogeneity. As well as traditional aspects of heterogeneity (language, platform, etc.), middleware providers must also deal with increasing heterogeneity of application domains (pervasive, multimedia, mobile, Grid, etc.) as well as similar rises in heterogeneity in the deployment environment (wireless, wired, ad-hoc, etc.). Furthermore, there is a need to support a wider variety of non-functional requirements in areas such as security and dependability, with more specialised solutions emerging, for example, in areas such as pervasive computing. It is now clear that middleware providers are struggling with such extreme heterogeneity and rather provide platforms that are overly bloated and complex to deal with the variety of situations where they might be used. It is equally clear that this is unsatisfactory and that a major paradigm shift is required to cater for such changing operational conditions.The middleware community is reacting to these challenges and there is now strong interest in reflective middleware as a technique to support more configurability, and indeed reconfigurability. For the purposes of this proposal, we focus exclusively on the problems of configurable middleware and, in particular, how middleware families can be generated using the inherent support provided by reflection. However, there is an element of complexity in dealing with the flexibility that reflection offers. In is therefore imperative that in parallel with developments in reflective middleware, we also study tools and techniques that support the automatic or semi-automatic generation of middleware families from higher level specifications. In this project, we propose to study the marriage of three areas of technology in meeting this challenge:1. Reflective middleware as discussed above;2. Model driven engineering (MDE) to support the automatic construction of complex software from models (in our case middleware);3. Aspect-oriented software development (AOSD) to provide a natural separation of concerns both in terms of the models and the resultant platform.This needs close co-operation between the different communities. We are fortunate at Lancaster to have internationally leading activity in the areas of (reflective) middleware and AOSD. This proposal is concerned with supplementing these skills by bringing in Prof. Robert France as a visiting researcher to the department for a period of 5 months to complete our coverage of the three areas (Robert is a leading researcher in MDE).