A Model-Based Approach to Managing Feature Binding Time in Software Product Line Engineering

Software Product Line Engineering (SPLE) is a software reuse paradigm for developing software products, from managed reusable assets, based on analysis of commonality and variability (C & V) of a product line. Many approaches of SPLE use a feature as a key abstraction to capture the C&V. Recently, there have been increasing demands for the provision of flexibility about not only the variability of features but also the variability of when features should be selected (i.e., variability on feature binding times). Current approaches to support variations of feature binding time mostly focused on ad hoc implementation mechanisms. In this paper, we first identify the challenges of feature binding time management and then propose an approach to analyze the variation of feature binding times and use the results to specify model-based architectural components for the product line. Based on the specification, components implementing variable features are parameterized with the binding times and the source codes for the components and the connection between them are generated

Supporting the automated generation of modular product line safety cases

Abstract The effective reuse of design assets in safety-critical Software Product Lines (SPL) would require the reuse of safety analyses of those assets in the variant contexts of certification of products derived from the SPL. This in turn requires the traceability of SPL variation across design, including variation in safety analysis and safety cases. In this paper, we propose a method and tool to support the automatic generation of modular SPL safety case architectures from the information provided by SPL feature modeling and model-based safety analysis. The Goal Structuring Notation (GSN) safety case modeling notation and its modular extensions supported by the D-Case Editor were used to implement the method in an automated tool support. The tool was used to generate a modular safety case for an automotive Hybrid Braking System SPL

A Brief Survey on Product Derivation Methods in Software Product Line

Product Derivation represents one of the main challenges that a Software Product Line (SPL) faces. Deriving individual products from shared software assets is a time-consuming and an expensive activity. Until now, only few works addressed, in a limited context, a partial evaluation of a reduced number of proposed derivation approaches. The main objective of such studies was the comparison of a proposed approach regarding two or three approaches. The purpose of the study reported in this paper is to set up a framework oriented to evaluate and compare existing SPL derivation approaches. The proposed framework uses a number of criteria which help understanding the capabilities and highlight the strength and the weakness of each SPL derivation approach

Systematic evaluation of software product line architectures

The architecture of a software product line is one of its most important artifacts as it represents an abstraction of the products that can be generated. It is crucial to evaluate the quality attributes of a product line architecture in order to: increase the productivity of the product line process and the quality of the products; provide a means to understand the potential behavior of the products and, consequently, decrease their time to market; and, improve the handling of the product line variability. The evaluation of product line architecture can serve as a basis to analyze the managerial and economical values of a product line for software managers and architects. Most of the current research on the evaluation of product line architecture does not take into account metrics directly obtained from UML models and their variabilities; the metrics used instead are difficult to be applied in general and to be used for quantitative analysis. This paper presents a Systematic Evaluation Method for UML-based Software Product Line Architecture, the SystEM-PLA. SystEM-PLA differs from current research as it provides stakeholders with a means to: (i) estimate and analyze potential products; (ii) use predefined basic UML-based metrics to compose quality attribute metrics; (iii) perform feasibility and trade-off analysis of a product line architecture with respect to its quality attributes; and, (iv) make the evaluation of product line architecture more flexible. An example using the SEI’s Arcade Game Maker (AGM) product line is presented as a proof of concept, illustrating SystEM-PLA activities. Metrics for complexity and extensibility quality attributes are defined and used to perform a trade-off analysis

Recombinant Service Systems Engineering

Although many methods have been proposed for engineering service systems and customer solutions, most of these approaches give little consideration to recombinant service innovation. Recombinant innovation refers to reusing and integrating resources that were previously unconnected. In an age of networked products and data, we can expect that many service innovations will be based on adding, dissociating, and associating existing value propositions by accessing internal and external resources instead of designing them from scratch. The purpose of this paper is to identify if current service engineering approaches account for the mechanisms of recombinant innovation and to design a method for recombinant service systems engineering. In a conceptual analysis of 24 service engineering methods, the study identified that most methods (1) focus on designing value propositions instead of service systems, (2) view service independent of physical goods, (3) are either linear or iterative instead of agile, and (4) do not sufficiently address the mechanisms of recombinant innovation. The paper discusses how these deficiencies can be remedied and designs a revised service systems engineering approach that reorganizes service engineering processes according to four design principles. The method is demonstrated with the recombinant design of a service system for predictive maintenance of agricultural machines

Planning strategically, designing architecturally : a framework for digital library services

In an era of unprecedented technological innovation and evolving user expectations and information seeking behaviour, we are arguably now an online society, with digital services increasingly common and increasingly preferred. As a trusted information provider, libraries are in an advantageous position to respond, but this requires integrated strategic and enterprise architecture planning, for information technology (IT) has evolved from a support role to a strategic role, providing the core management systems, communication networks, and delivery channels of the modern library. Further, IT components do not function in isolation from one another, but are interdependent elements of distributed and multidimensional systems encompassing people, processes, and technologies, which must consider social, economic, legal, organisational, and ergonomic requirements and relationships, as well as being logically sound from a technical perspective. Strategic planning provides direction, while enterprise architecture strategically aligns and holistically integrates business and information system architectures. While challenging, such integrated planning should be regarded as an opportunity for the library to evolve as an enterprise in the digital age, or at minimum, to simply keep pace with societal change and alternative service providers. Without strategy, a library risks being directed by outside forces with independent motivations and inadequate understanding of its broader societal role. Without enterprise architecture, it risks technological disparity, redundancy, and obsolescence. Adopting an interdisciplinary approach, this conceptual paper provides an integrated framework for strategic and architectural planning of digital library services. The concept of the library as an enterprise is also introduced

Trusted product lines

This thesis describes research undertaken into the application of software product line approaches to the development of high-integrity, embedded real-time software systems that are subject to regulatory approval/certification. The motivation for the research arose from a real business need to reduce cost and lead time of aerospace software development projects. The thesis hypothesis can be summarised as follows: It is feasible to construct product line models that allow the specification of required behaviour within a reference architecture that can be transformed into an effective product implementation, whilst enabling suitable supporting evidence for certification to be produced. The research concentrates on the following four main areas: 1. Construction of an argument framework in which the application of product line techniques to high-integrity software development can be assessed and critically reviewed. 2. Definition of a product-line reference architecture that can host components containing variation. 3. Design of model transformations that can automatically instantiate products from a set of components hosted within the reference architecture. 4. Identification of verification approaches that may provide evidence that the transformations designed in step 3 above preserve properties of interest from the product line model into the product instantiations. Together, these areas form the basis of an approach we term “Trusted Product Lines”. The approach has been evaluated and validated by deployment on a real aerospace project; the approach has been used to produce DO-178B/ED-12B Level A applications of over 300 KSLOC in size. The effect of this approach on the software development process has been critically evaluated in this thesis, both quantitatively (in terms of cost and relative size of process phases) and qualitatively (in terms of software quality). The “Trusted Product Lines” approach, as described within the thesis, shows how product line approaches can be applied to high-integrity software development, and how certification evidence created and arguments constructed for products instantiated from the product line. To the best of our knowledge, the development and effective application of product line techniques in a certification environment is novel and unique

Adaptable software reuse:binding time aware modelling language to support variations of feature binding time in software product line engineering

Software product line engineering (SPLE) is a paradigm for developing a family of software products from the same reusable assets rather than developing individual products from scratch. In many SPLE approaches, a feature is often used as the key abstraction to distinguish between the members of the product family. Thus, the sets of products in the product line are said to have ’common’ features and differ in ’variable’ features. Consequently, reusable assets are developed with variation points where variant features may be bound for each of the diverse products. Emerging deployment environments and market segments have been fuelling demands for adaptable reusable assets to support additional variations that may be required to increase the usage-context of the products of a product line. Similarly, feature binding time - when a feature is included in a product and made available for use - may vary between the products because of uncertain market conditions or diverse deployment environments. Hence, variations of feature binding time should also be supported to cover the wide-range of usage-contexts. Through the execution of action research, this thesis has established the following: Language-based implementation techniques, that are specifically proposed to implement variations in the form of features, have better modularity but are not better than the existing classical technique in terms of modifiability and do not support variations in feature binding time. Similarly, through a systematic literature review, this thesis has established the following: The different engineering approaches that are proposed to support variations of feature binding time are limited in one of the following ways: a feature may have to be represented/implemented multiple time, each for a specific binding time; The support is only to execution context and therefore limited in scope; The support focuses on too fine-grained model elements or too low-level of abstraction at source-codes. Given the limitations of the existing approaches, this thesis presents binding time aware modelling language that supports variations of feature binding time by design and improves the modifiability of reusable assets of a product line