Building software product lines (SPLs) with features is a challenging task. Many SPL implementations support features with coarse granularitye.g., the ability to add and wrap entire methods. However, fine-grained extensions, like adding a statement in the middle of a method, either require intricate workarounds or obfuscate the base code with annotations. Though many SPLs can and have been implemented with the coarse granularity of existing approaches, fine-grained extensions are essential when extracting features from legacy applications. Furthermore, also some existing SPLs could benefit from fine-grained extensions to reduce code replication or improve readability. In this paper, we analyze the effects of feature granularity in SPLs and present a tool, called Colored IDE (CIDE), that allows features to implement coarsegrained and fine-grained extensions in a concise way. In two case studies, we show how CIDE simplifies SPL development compared to traditional approaches.

No abstract

Abstract. A software product line (SPL) is a family of related program variants in a well-defined domain, generated from a set of features. A fundamental difference from classical application development is that engineers develop not a single program but a whole family with hundreds to millions of variants. This makes it infeasible to separately check every distinct variant for errors. Still engineers want guarantees on the entire SPL. A further challenge is that an SPL may contain artifacts in different languages (code, documentation, models, etc.) that should be checked. In this paper, we present CIDE, an SPL development tool that guarantees syntactic correctness for all variants of an SPL. We show how CIDE's underlying mechanism abstracts from textual representation and we generalize it to arbitrary languages. Furthermore, we automate the generation of plug-ins for additional languages from annotated grammars. To demonstrate the language-independent capabilities, we applied CIDE to a series of case studies with artifacts written in Java, C++, C, Haskell, ANTLR, HTML, and XML.

No abstract

Abstract. Feature-oriented programming (FOP) is an extension of object-oriented programming to support software variability by refining existing classes and methods. In order to increase the reliability of all implemented program variants, we integrate design by contract (DbC) with FOP. DbC is an approach to build reliable object-oriented software by specifying methods with contracts. Contracts are annotations that document and formally specify behavior, and can be used for formal verification of correctness or as test oracles. We present and discuss five approaches to define contracts of methods and their refinements in FOP. Furthermore, we share our insights gained by performing five case studies. This work is a foundation for research on the analysis of feature-oriented programs (e.g., for verifying functional correctness or for detecting feature interactions).