Self-adaptive software (SAS) is gaining popularity as it can reconfigure itself in response to the dynamic changes in the operational context or itself. However, early modeling and formal analysis of SAS systems becomes increasingly difficult, as the system scale and complexity is rapidly increasing. To tackle the modeling difficulty of SAS systems, we present a refinement-based modeling and verification approach called EasyModel. EasyModel integrates the intuitive Unified Modeling Language (UML) model with the stepwise refinement Event-B model. Concretely, EasyModel: 1) creates a UML profile called AdaptML that provides an explicit description of SAS characteristics, 2) proposes a refinement modeling mechanism for SAS systems that can deal with system modeling complexity, 3) offers a model transformation approach and bridges the gap between the design model and the formal model of SAS systems, and 4) provides an efficient way to verify and guarantee the correct behaviour of SAS systems. To validate EasyModel, we present an example application and a subject-based experiment. The results demonstrate that EasyModel can effectively reduce the modeling and formal verification difficulty of SAS systems, and can incorporate the intuitive merit of UML and the correct-by-construction merit of Event-B.

中文翻译：

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EasyModel：一种基于细化的自适应软件建模和验证方法

自适应软件 (SAS) 越来越受欢迎，因为它可以重新配置自身以响应操作环境或自身的动态变化。然而，随着系统规模和复杂性的迅速增加，SAS 系统的早期建模和形式分析变得越来越困难。为了解决 SAS 系统的建模困难，我们提出了一种基于细化的建模和验证方法，称为 EasyModel。EasyModel 将直观的统一建模语言 (UML) 模型与逐步细化的 Event-B 模型相集成。具体来说，EasyModel：1) 创建了一个名为 AdaptML 的 UML 配置文件，它提供了对 SAS 特性的明确描述，2) 为 SAS 系统提出了一种可以处理系统建模复杂性的细化建模机制，3) 提供了一种模型转换方法，弥合了 SAS 系统的设计模型和形式模型之间的差距，以及 4) 提供了一种有效的方法来验证和保证 SAS 系统的正确行为。为了验证 EasyModel，我们提供了一个示例应用程序和一个基于主题的实验。结果表明，EasyModel 可以有效降低 SAS 系统的建模和形式验证难度，并且可以结合 UML 的直观优点和 Event-B 的正确构造优点。