Supporting Multi-Domain Model Management

Model-driven engineering has been used in different domains such as software engineering, robotics, and automotive. This approach has models as the primary artifacts, and it is expected to improve quality of system specification and design, as well as the communication among the development team. Managing models that belong to the same domain might not be a complex task because of the features provided by the available development tools. However, managing interrelated models of different domains is challenging. A robot is an example of such a multi-domain system. To develop it one might need to combine models created by experts from mechanics, electronics and software domains. These models might be created using domain specific tools of each domain, and a change in one model of one domain might impact a model from a different domain causing inconsistency in the entire system. This thesis therefore aims to facilitate the evolution of the models in this multi-domain setting. It starts with a systematic literature review in order to identify the open issues, and strategies used to manage models from different domains. We identified that making explicit the relationship between models from different domains can support the models maintenance, making it easy to recognize affected models because of a change. The following step was to investigate ways of extracting information from different engineering models that were created using different modeling notations. For this goal, we required a uniform approach that would be independent from the peculiarities of the notations. This uniform approach can only be based on elements typically present in various modeling notations, i.e., text, boxes, and lines. Thus, we investigated the suitability of optical character recognition (OCR) for extracting textual elements from models from different domains. We also identified the common errors made by the off-the-shelf OCR services, and we proposed two approaches to correct one of these errors. After that, we used name matching techniques on the textual elements extracted by OCR to identify relationships between models from different domains. To conclude, we created an infrastructure that combines all the previous elements into one single tool that can also store the relationships in a structured manner making it easier to maintain the consistency of an entire system. We evaluated it by means of an observational study with a multidisciplinary team that builds autonomous robots designed to play football

Recovery of Software Architecture from Code Repositories

The goal of this work is to create an approach and tool that will a) extract architectural-significant information from code repositories, namely from resources such as dockerfiles and terraform configurations; b) use of the extracted information to synthesise architectural models that will be kept in-sync with the code repositories automatically; c) support the mechanisms that will allow a team to supply any additional details to the architectural model that can't be inferred directly from the repositories. This approach is expected to reduce information redundancy between code and textual documentation, and still allow an integrated and machine-readable view of the overall software architecture of a system.Architecture can be the result of multiple intangibly connected parts spread across source code and other development artifacts. This makes it difficult to describe the architecture without resourcing to auxiliary documentation that puts this information together. Most of the times, this documentation is manually created, render it a costly process which overtime starts to be desregarded and the documentation becomes out of date and sometimes obsolete. Automating the recovery of the architecture using artifacts that are already present on the source code could potentially improve the way documentation is updated and used

Role-based Adaptation of Business Reference Models to Application Models: An Enterprise Modeling Methodology for Software Construction

Large software systems are in need of a construction plan to determine and define every concept and element used in order to not end up in complex, unusable, and cost-intensive systems. Different modeling languages, like UML, support the development of these construction plans and visualize them for the system’s stakeholders. Reference models are a specific kind of construction plan, used as templates for information systems and already capture business domain knowledge for reuse and tailoring. By adaptation, reference models are tailored to enterprise-specific application models, which can be used for software construction and maintenance. However, current adaptation methods suffer from the limitations of pure object-oriented development (e.g., identity issues, large inheritance trees, and inflexibility). In this thesis, the usage of roles as the sole adaptation mechanism is proposed to solve these challenges. With the help of conceptual roles, it is possible to create rich model variations and adaptations from existing (industry standard) reference models, and it is simpler to react to model evolution and changing business logic. Adaptations can be specified with more precision by maintaining or even increasing the model’s expressiveness. As a consequence, the role-enriched final application model can be used to describe software systems in more detail, with different perspectives, and, if available, can be implemented with a role supporting programming language. However, even without this step, the application model itself will provide valuable insights into the overall construction plan of a software system by the combination of structure and behavior and a clear separation of relatively stable domain knowledge from its use case specific adaptation

A Framework for Seamless Variant Management and Incremental Migration to a Software Product-Line

Context: Software systems often need to exist in many variants in order to satisfy varying customer requirements and operate under varying software and hardware environments. These variant-rich systems are most commonly realized using cloning, a convenient approach to create new variants by reusing existing ones. Cloning is readily available, however, the non-systematic reuse leads to difficult maintenance. An alternative strategy is adopting platform-oriented development approaches, such as Software Product-Line Engineering (SPLE). SPLE offers systematic reuse, and provides centralized control, and thus, easier maintenance. However, adopting SPLE is a risky and expensive endeavor, often relying on significant developer intervention. Researchers have attempted to devise strategies to synchronize variants (change propagation) and migrate from clone&own to an SPL, however, they are limited in accuracy and applicability. Additionally, the process models for SPLE in literature, as we will discuss, are obsolete, and only partially reflect how adoption is approached in industry. Despite many agile practices prescribing feature-oriented software development, features are still rarely documented and incorporated during actual development, making SPL-migration risky and error-prone.Objective: The overarching goal of this PhD is to bridge the gap between clone&own and software product-line engineering in a risk-free, smooth, and accurate manner. Consequently, in the first part of the PhD, we focus on the conceptualization, formalization, and implementation of a framework for migrating from a lean architecture to a platform-based one.Method: Our objectives are met by means of (i) understanding the literature relevant to variant-management and product-line migration and determining the research gaps (ii) surveying the dominant process models for SPLE and comparing them against the contemporary industrial practices, (iii) devising a framework for incremental SPL adoption, and (iv) investigating the benefit of using features beyond PL migration; facilitating model comprehension.Results: Four main results emerge from this thesis. First, we present a qualitative analysis of the state-of-the-art frameworks for change propagation and product-line migration. Second, we compare the contemporary industrial practices with the ones prescribed in the process models for SPL adoption, and provide an updated process model that unifies the two to accurately reflect the real practices and guide future practitioners. Third, we devise a framework for incremental migration of variants into a fully integrated platform by exploiting explicitly recorded metadata pertaining to clone and feature-to-asset traceability. Last, we investigate the impact of using different variability mechanisms on the comprehensibility of various model-related tasks.Future work: As ongoing and future work, we aim to integrate our framework with existing IDEs and conduct a developer study to determine the efficiency and effectiveness of using our framework. We also aim to incorporate safe-evolution in our operators

Code Generation from UML Models

Creating a generic, object-oriented, component-based, transactional business system, which covers the whole lifecycle, is possible only with the integration of commercial tools, component technologies, newly developed class libraries and by using code generators. Most of the recently used tools for development techniques are focusing on only one of the layers of the model from the code generation point of view. As a consequence, the inter-layer connections are lost in the generated code. In this article, we describe a code generator technique which uses a UML model as a starting point and generates several layers directly. While generating the code, it preserves the original interlayer relationships originated in the model. Based on our experiences with 4GL systems it is obvious that there is a need to provide customisation in the generated code. We offer a multi-paradigm approach [1] to let the developer choose the appropriate solution for her or his implementation

Quality Assurance of Software Models - A Structured Quality Assurance Process Supported by a Flexible Tool Environment in the Eclipse Modeling Project

The paradigm of model-based software development (MBSD) has become more and more popular since it promises an increase in the efficiency and quality of software development. In this paradigm, software models play an increasingly important role and software quality and quality assurance consequently leads back to the quality and quality assurance of the involved models. The fundamental aim of this thesis is the definition of a structured syntax-oriented process for quality assurance of software models that can be adapted to project-specific and domain-specific needs. It is structured into two sub-processes: a process for the specification of project-specific model quality assurance techniques, and a process for applying them on concrete software models within a MBSD project. The approach concentrates on quality aspects to be checked on the abstract model syntax and is based on quality assurance techniques model metrics, smells, and refactorings well-known from literature. So far, these techniques are mostly considered in isolation only and therefore the proposed process integrates them in order to perform model quality assurance more systematically. Three example cases performing the process serve as proof-of-concept implementations and show its applicability, its flexibility, and hence its usefulness. Related to several issues concerning model quality assurance minor contributions of this thesis are (1) the definition of a quality model for model quality that consists of high-level quality attributes and low-level characteristics, (2) overviews on metrics, smells, and refactorings for UML class models including structured descriptions of each technique, and (3) an approach for composite model refactoring that concentrates on the specification of refactoring composition. Since manually reviewing models is time consuming and error prone, several tasks of the proposed process should consequently be automated. As a further main contribution, this thesis presents a flexible tool environment for model quality assurance which is based on the Eclipse Modeling Framework (EMF), a common open source technology in model-based software development. The tool set is part of the Eclipse Modeling Project (EMP) and belongs to the Eclipse incubation project EMF Refactor which is available under the Eclipse public license (EPL). The EMF Refactor framework supports both the model designer and the model reviewer by obtaining metrics reports, by checking for potential model deficiencies (called model smells) and by systematically restructuring models using refactorings. The functionality of EMF Refactor is integrated into standard tree-based EMF instance editors, graphical GMF-based editors as used by Papyrus UML, and textual editors provided by Xtext. Several experiments and studies show the suitability of the tools for supporting the techniques of the structured syntax-oriented model quality assurance process

Polyglot software development

The languages we choose to design solutions influence the way we think about the problem, the words we use in discussing it with colleagues, the processes we adopt in developing the software which should solve that problem. Therefore we should strive to use the best language possible for depicting each facet of the system. To do that we have to solve two challenges: i) first of all to understand merits and issues brought by the languages we could adopt and their long reaching effects on the organizations, ii) combine them wisely, trying to reduce the overhead due to their assembling. In the first part of this dissertation we study the adoption of modeling and domain specific languages. On the basis of an industrial survey we individuate a list of benefits attainable through these languages, how frequently they can be reached and which techniques permit to improve the chances to obtain a particular benefit. In the same way we study also the common problems which either prevent or hinder the adoption of these languages. We then analyze the processes through which these languages are employed, studying the relative frequency of the usage of the different techniques and the factors influencing it. Finally we present two case-studies performed in a small and in a very large company, with the intent of presenting the peculiarities of the adoption in different contexts. As consequence of adopting specialized languages, many of them have to be employed to represent the complete solution. Therefore in the second part of the thesis we focus on the integration of these languages. Being this topic really new we performed preliminary studies to first understand the phenomenon, studying the different ways through which languages interact and their effects on defectivity. Later we present some prototypal solutions for i) the automatic spotting of cross-language relations, ii) the design of language integration tool support in language workbenches through the exploitation of common meta-metamodeling. This thesis wants to offer a contribution towards the productive adoption of multiple, specific languages in the same software development project, hence polyglot software development. From this approach we should be able to reduce the complexity due to misrepresentation of solutions, offer a better facilities to think about problems and, finally to be able to solve more difficult problems with our limited brain resources. Our results consists in a better understanding of MDD and DSLs adoption in companies. From that we can derive guidelines for practitioners, lesson learned for deploying in companies, depending on the size of the company, and implications for other actors involved in the process: company management and universities. Regarding cross-language relations our contribution is an initial definition of the problem, supported by some empirical evidence to sustain its importance. The solutions we propose are not yet mature but we believe that from them future work can stem